Unable to register as the PAH

I’m having this same exact issue. I have called customer support and they said I had to take my social into the store and have a T-Mobile rep confirm it before they could fix it. (I did not have this issue until I added a second line). Once in store, I explained what happened and a rep called customer service to explain why I was there. After explaining my situation once again, they told me that there was nothing they could do and I had to write a letter to T-Mobile in New Mexico (I took my ID, Social security card and birth certificate to the store, how could they not help!?). Snail mail is ridiculous when anyone can write a letter and claim to be me. It’s different when you show up with a photo ID, birth certificate and social security card. I went home very dissatisfied and disappointed with the lack of customer service I received in store. I called the CSL again and was told I had to go back in store and take my documents again and the reps had to call them, then be redirected to consumers credit department (where they should be able to fix my issue). I would have never left my last carrier if I knew this was going to happen. So far no resolution for my own account that I created and pay the bill for. Ridiculous. I feel for everyone experiencing this same issue. I’m amazed at how some got this resolved in a matter of minutes. 

I called 611. They were able to get it taken care of. 

Same happened to me as well. Got it fixed’ 

Boo, happened to me, bad start to my t mobile days

Oh, man! That's great news. I hope this is the one and only glitch, too -- and I'm sorry that there had to be a glitch at all, but glad that our Care team was able to square this away so quickly! Thanks for coming back to let us know! 😊

Hey, @magenta4835452​! First off, thanks for joining TMO and our Support Community! I'm sorry that the welcome you're receiving hasn't been free of snags!
It sounds like you're following the correct steps to establish your line as the PAH -- what happens once you enter the information? Do you see an error message; or is the line view simply not changed? What browser(s) have you tried to use to complete this step so far?

One thing I want to call out because you mentioned the military discount (hooray! 😀) -- I know that the PAH on accounts that have verified eligibility has to be the military member. If that's you, this is definitely something that we need to clear up ASAP!
While we can't take a look from here, our internal teams with account access do have access to a tool we can use to manually establish the correct PAH. When you've reached out to our Care teams, have we been attempting to complete this step and advising you of the timeline after making changes -- or just explaining the standard timelines, but not using the tool?

Thanks again for posting, and sorry for all of the questions!