Can't connect to T-Mobile update server

Thanks for reaching out, much appreciated. Here's a chronology which I hope

will prove helpful:

Until about 2-3 weeks ago, I had no issues downloading either security

patches or Android system updates from the T-Mobile server. I always do

these updates in my home, where I have 5 bars of T-Mobile signal and a

Google mesh router from which Ookla Speedtest registers approximately 175

mbps.

Approximately 2-3 weeks ago, I noticed that when I went to *settings>software

update>download and install, *my S9 would report "checking for updates,"

and the spinning wheel would turn for a long time (well over 3 minutes)

until I got a message indicating "Couldn't download update...Unable to

reach the server..."

I called T-Mobile tech support for help with this matter. The technician

told me he thought the problem was with the phone, not the T-Mobile server,

so he patched me over to a Samsung technician. The Samsung technician asked

me to download "smart-tutor so he could control my phone remotely. When he

determined there was nothing he could do to help, he gave me the address of

an authorized Samsung repair shop (ubreakifix) and told me to request a

"flash" update, which would solve the problem but wipe my phone clean and

leave me with hours of reconstruction. The phone was indeed "fixed" (i.e. I

could reach the T-Mobile server as I walked down the street from the repair

shop), but by the next morning, I was once again unable to connect with the

T-Mobile server.

Two days later, I walked into my local T-Mobile store to see if they had

any thoughts about what to do. The young lady behind the counter asked me

to show her the problem, and when I went to *settings>software

update>download and install, *I had no difficulty connecting to the

T-Mobile server (on the T-Mobile network, not on the store Wi-Fi). So,

feeling that the problem might actually have resolved on its own, I went

home with my phone. The next morning, and up to this very moment, I still

cannot connect with the T-Mobile server.

It is difficult for me to believe that there is a problem with the phone

because I never have any difficulty downloading updates for my Android

apps, which I do on a regular basis. Any help you might be able to provide

would be greatly appreciated!

Thanks.

When I go to Settings>Software update, I have only two choices...the first is "download and install," and the second (which is greyed out and unavailable) is "last update." There is another setting, in a different area of settings, where I can choose to access the internet via Wi-Fi only, but that one is set to allow access via T-Mobile and Wi-Fi.

Thanks again for staying with me on this. This screenshot shows you what I

see.