Unlocked phones

  • 4 November 2016
  • 18 replies

I am having some issues with unlocked phones.


I have several of devices and none of the work properly on T-Mobile.   When I call support they basically blow me off because I am not using a T-Mobile branded handset.   They also assume that when you say "unlocked" phone that you have taken another carriers phone and had it SIM unlocked and are taking the phone from another carrier to T-Mobile.


What support also does not seem to get is that there is a wide variety of factory unlocked phones that are designed for the North American GSM frequencies and some of these phones actually have features such as Band 12, VOLTE and WiFi calling.


2 phones I am having trouble with specifically are the BLU R1 HD and the Alcatel Pixi4 (5).


The BLU does not support Band 12/Volte.   The Alcatel does support Band 12.Volte.


The Alcatel seems to work fine when it is on a 4G LTE single and the VOLTE indicator is lit.


When these phones are showing that they are on a 4G signal, when you call the phone,the phone sometimes will not ring.   This is not consistent.  About half the time the phone will ring, but the other half the time the phone does nothing and the call rolls to voicemail.


When the phone is called you can watch the signal icon change from 4G to 3G and the phone MIGHT begin to ring.   Sometimes the 4G indicator fails to change at all.   I have this issue at home, in the car and at work.   I do not think this is a signal quality issue.


Both phones have no problem making outbound calls.


I setup a new line of service on a new SIM and I have the same issue with the new number/account.  I also borrowed a T-Mobile SIM from a buddy, and it had the same issue.


I went to ATT and setup a new prepaid account with them and these phones work perfectly. I would move my business to ATT but their data speeds are far too slow.


What can be done to rectify this issue?   I think there is a problem with the 4G/3G handoff in my area, but I can't get T-Mobile to take this issue seriously.


Best answer by magentatechie 21 June 2019, 21:43

View original

18 replies

Userlevel 3
Badge +7

Well from Alcatel's website the Pixi4 (5) doesn't actually support any of T-Mobile's LTE frequencies; (2, 4, & 12)

GSM quadband 850/900/1800/1900. UMTS 850/900/1900/2100. HSPA+ (42M bit/s DL. 11Mbit/s UL) LTE B1/3/7/8/20/28A

Also it doesn't support T-Mobile's primary HSPDA+ network which runs on the 1700/2100 Band 4.  Also T-Mobile really doesn't have a 3G network per se.  Their HSPDA+42 network (4G non LTE) is just backward compatible to HSPDA+21, HSPDA+ or HSPDA (3G) but is all the same network and radios on the tower.

Here is a list of the T-Mobile frequencies used;

Supported T-Mobile networks

You are looking at the specs for the global model.   I don't have that.


GSM 850/900/1800/1900

3G: B2/4/5; LTE: B2/4/5/7/12/17


Userlevel 3
Badge +7

Ok, even with those specs it doesn't support T-Mobile's HSPDA+ primary

frequency (3G, 4G non LTE) which is Band 4 1700/2100 so if it drops off LTE

it will drop all the way to 2G. If it can't maintain or complete a VoLTE

call T-Mobile branded devices will roll back to 4G non LTE, maybe because

it can't go find anything there it gets hung??

Okay I was under the understating that G3 B4 is 1700/2100.

So then why does the BLU R1 HD have the same fault?

TechnologyGSM / HSPA / LTE
2G bandsGSM 850 / 900 / 1800 / 1900 - SIM 1 & SIM 2
3G bandsHSDPA 850 / 1700(AWS) / 1900 / 2100
4G bandsLTE band 2(1900), 4(1700/2100), 7(2600), 17(700)
Userlevel 4

Hey mausmang

I wanted to check and see if it was possible for you to try your SIM card in your buddies phone that let you barrow his SIM card. If his is a T-Mobile branded phone and the issue persists with your SIM in his phone, we can safely say that the issue with the network rather than the phone. If the issue is with the network, our tech support team can open an engineering ticket for you to have this looked at.

Been there done that.  Ticket 13895274 was opened on Oct 28.  They don't take problems with unlocked phones seriously.  I can tell you that I just picked up a LeEco S3 and it works flawlessly.   Also I can report that all of the phones that are problematic have Mediatek chips.   Phones with Qualcomm chips have no problems.

Userlevel 4

So with non-T-Mobile phones is is hard to say if they are going to work properly with all aspects of our network as they were not designed with the purpose of being used on our network. We ask that you test the sim in a known working T-Mobile phone so that we can see if the network is at fault as there are to many variables with non-T-Mobile phones.

Yes I have done this.  My SIM works fine in a T-Mobile branded phone.   But you know as well as I, that this SIM should work in ANY unlocked GSM phone provided that it supports US/T-Mobile frequencies.   Obviously this is not the case.   Doesn't matter now anyway....I have switched to another carrier and now all is well.

Understood, but we bought 3 LG V10's two years ago, and NONE of them lasted the two years of the contract without giving us black screens of death or, worse, green screen with hardware diagnostics.  These phones were not abused, my phone looks absolutely perfect, no scratches.  I did not drop it.  I was using it one minute, set it on the coffee table, got up a little while later and pushed the button to turn on the display, and nothing.

The point is not to whine and complain about the V10's, but I will never buy an LG phone again, and once you eliminate LG from T-Mobile's line up, there's really only Samsung and some other scraps.  IOW, not a great selection.  So my cheap unlocked phone I got on Amazon will not send pictures in text messages, I cannot access my voice mail without typing in my whole 10 digit number and code, I cannot create a mobile hot-spot.

Unlike most consumers, I love my phone company - I hate the phones they are offering.  So what am I supposed to do?  Hardware-wise, I'm really happy with my HTC one M8 I got as a replacement.  Unfortunately, I will have to get a phone I'm wary of getting (Samsung - too many complaints about the screen - and the fourth phone I bought two years was an S5 and it's screen broke, so no phones lasted two years).

Userlevel 3
Badge +7

Yeah the LG fiasco with the boot loop on the G4 (and the V10 although they still hem and haw about that one) was handled very poor by LG and it will hurt them for some time.  T-Mobile (and Verizon) tried a few years ago to give Sony a chance to re-enter the US market and both got s******d for doing it as it didn't go as well as Sony had hoped so they just pulled the plug on support and everything and pulled out leaving just the TMO and VZW versions of the Z3 without the OS update that year. So then you have Google and the Pixel but VZW keeps paying to be exclusive on it and while it works on TMO you have to go to Google or VZW to get one so you can't EIP it or JUMP to it. TMO used to be one of HTC's biggest customers but now HTC is barely treading water so no US carrier sells their phones directly anymore.  After that you have some smaller 3rd party players but nothing that any of the US carriers will carry and my guess is the individual tailoring that they want or in the case of TMO need so the device can take advantage of all the "features" the TMO network supports.  So yeah pretty much leaves Samsung at that point;  I have had every S since the 2 and have had 2 Notes one being the Edge and the only 2 screens I have broken (well 1 for me 1 for my ex-wife) were clearly our issue.  Mine S6 came out of my shirt pocket when I bent over and it went face first with no case onto the pavement, it didn't even shatter since the GG4 it had doesn't shatter it just got a crack which I couldn't even feel on the surface.  The other was an S5 also but that one my wife (at the time) was using my phone and trying to walk and talk then tripped and rather than let the phone go used it to break her fall and shattered the screen. I have the S8 now and love it other than since I preordered and it showed as larger than my S7+ I got the regular S8 when actually getting to look at both phones physically would have gotten the 8+ since the new dimensions make the + not seem so big even though the screen size is actually larger.

The picture message issue there is a way to get that to work it is just a matter of tweaking the settings and APN.  I am surprised with a TMO SIM card in it and on TMO network you should be able to dial the short code number for VM (123 I believe) and have never had anyone try to install the visual voicemail app on a non branded phone. I don't even use regular VM, I just use the app since it is so much easier.  The hotspot yeah that one sucks but it's more for security and or abusers that it's locked out and requires coding in the OS for security so that folks that don't have hotspot or a small amount can't use 3rd party software to get around it, so as usually the handful of cheats/abusers screw it up for everyone.

The problem is not your phone; it is greedy T-Mobile.

I have 2 unlocked phones with T-mobile and those 2 all have multiple issues with T-Mobile network.

Their functions do not work; they lose connection and network; constantly getting no Notwork.

When I call T-Mobile, they keep trying to put the blame on Non-T-mobile phone.  I have to call their technical support every week. Only the phone that I brought from them functions properly.


By selling their own version of phones at full retail price, they make extra money.

T-Mobile is turning into a corrupt company. it is like you buy a Ford car and have to buy gasoline from Ford approved gas stations.

They advertise to bring your phone to us and you can use it; that is false advertising.

I hope soon, a good attorney takes T-Mobile to court.

Userlevel 1

Well I had a blue phone and also had issues with it on the t mobile network everything worked fine except data if I had less than three bars the internet pretty much was unusable it was an Blu energy which was an 4G only device. Just as you thought blu phone worked better on AT&T than on t mobile I was so eager to rid of it I brought an LG K7 no issues at all.

Userlevel 1

I live in Puerto Rico not in the states so this isn't a tmo issue it's more device related

Bought an unlocked Moto G7 phone recently and am having signal problems. Really don't understand, nor do I want to, most of this thread.  Can anyone tell me which carrier might work with my new phone?

Userlevel 4
Badge +10

Hey there!  Just checking, you are a current T-Mobile customer and having problem with your service using an unlocked Moto G7?  Have you checked your APN settings to make sure everything is set up properly?  (This may be located under Settings>Network & Internet>Mobile Network>Advanced>Access Point Names)

You should have an APN that is labeled as T-Mobile (or T-Mobile US LTE or something similar).  If you don't, you'll want to add it- select the big plus sign (or if you don't see one, tap the 3 dots in the upper right hand corner and select "Add New".  Input the following:

  • APN:
  • Proxy: Not set
  • Port: Not set
  • Username: Not set
  • Password: Not set
  • Server: Not set
  • MMSC:
  • MMS proxy: Not set
  • MMS port: 80
  • MCC: 310
  • MNC: 260
  • Authentication type: Not set
  • APN type: default,supl,hipri,fota,mms
  • APN protocol: IPv6
  • APN roaming protocol: IPv4
  • APN enable/disable: Enabled
  • MVNO type: None
  • MVNO value: Not set

Dear Magentatechie,


I hope that you are still on this community chat.

I have an unlocked Samsung, purchased in Asia, from a Samsung store.  When I put the tmobile SIM into it, I sometimes get a 4GLTE signal, but most often it is either E or no signal at all.

I tried following your suggestion.  First, I added a new APN as per your details. The phone did not save it.  

Since there was already an APN with “”, I edited it. I added the MMSC, and made a few other changes as per your instructions.  I saved it.  It has saved correctly,  But the phone does not allow me to select it.  So now, the phone has no data signal at all !!!!

 -- update --

I followed the instructions from T-Mobile’s BYOD page.

I was able to get the data connection back.  However, the signal is still just E.


Any help is much appreciated. 


please unlock iPhone 7 Plus

imei 355839089476545


Userlevel 7
Badge +16

please unlock iPhone 7 Plus

imei 355839089476545