5G internet cant rename SSID

Thanks for posting this update. I came across your post last night after receiving my replacement gateway and was having the exact same issue, although I did not have it a few days ago on the old gateway.

I asked them about the 192.168.12.1 providing no options other than status, and they told me it was removed from the Web GUI because people were getting hacked and have switched it to having network name and password changed in the app only (although it now doesn't work). I will try to find an old android that I have laying around and will see if that does the trick.

If for any reason your network speeds suddenly plummet (i was getting around 260 download/40 upload), and for the past week i'm getting 40/4 (sometimes I'm getting (7down / .6 up)) and they're unable to resolve it, your device may be overheating. I found threads regarding the device possible overheating - the solution seems to be buying a small modem/router fan to place underneath, or placing it on an a/c unit. Mine is in the window, but not in the sun as directed, so I have moved it as well. We will see.

Thanks for the update! you’ve saved me a lot of time.

I think ISPs try to make us seem like we need higher internet speeds than we actually do.

I'm still working with this SSID name change issue, and found that it may not be only the App on iOS, as I just went back to my previous gateway and was able to change the name from my iPhone. Unfortunately, I think i gave my old Androids away. I went into the settings on both devices and found that my old device is version 1.00.16, and my new one is 1.00.12. If you go into the Tmobile Home Internet App and go to 'More' → 'Gateway Information', you may be on the old firmware as well.

Now i'm trying to figure out how to upgrade the firmware. And I'm wondering if this firmware update had anything to do w/ the change in my internet speeds.

This has been a disaster.

As an update I resolved the issue by using an Android phone. I have an iPhone 12 Pro Max and for some reason the iOS app does not actually change the name or reboot the router. I used an old Pixel 2 XL I had laying around and it worked perfect. 
 

I don’t know how to tell T-Mobile to fix their iOS app but if they see this that was the issue. 

Good to know. I have mine in a window as directed but I fear it will probably overheat. We get a lot of sun where we live. I might just put a shelf on the wall next to the window and see if that works. The service is impressive so far. When I speed test it with 3 to 4 bars we get roughly 90Mbps down. Which honestly isn't very good for home internet. 
 

Somehow the modem must be able to allocate the 90Mbps individually to each device connected because I've had two computer downloading at 14Mbps, 3 iPads playing YouTube, two TVs playing Netflix and google stadia running and somehow it all works. We previously paid for 100Mbps through century link and it would barely run our ring doorbell. We switched to Xfinity 1.2Gbps and that does work well but it is very expensive. 
 

I'm only on day 2 but I've went from unimpressed to impressed. It seems to work well and despite speed testing at a relatively low speed it manages to work fine having 40ish devices connected and a family of 9 all using it simultaneously. How they do this …. I have no clue but I hope it continues to provide this performance. 

My modem firmware is 1.00.16. I have the black modem with the LCD screen on the front with 3 buttons. I've found the service is inconsistent. Yesterday it worked great. Today the speeds are hit and miss. For part of the day the internet will work great for everyone, and then at times it just crawls so slow. I'm wondering if it has to do with network congestion at the tower.

I finally got it straightened out. The firmware is updated overnight between 1-3am EST. I left the device (the same one that you have with the 3 buttons on the front) plugged in overnight and connected and I checked today and it's now on 1.00.16. I tried to rename the device and it worked perfectly. 

If your device hadn't sat overnight to update before trying to change the name, you might have been on .12 previously and then checked after it had already updated. If you're on .16 now and try it, the name change should work for you (although i know you've already changed it).

Today I'm at 90, but was told that there was an issue on my tower that is being worked. Normally I get 260-300. I did learn that if there is congestion, phones are prioritized over home internet (I didn't know this when I signed up), which could be the reason. My amazon component fan ($12) arrived today and I put it under it, but I honestly don't know if this will even make a difference since I'm not getting what I normally did. I had this service for 3 months always consistent and it just recently started acting weird w/ the large fluctuations in speed. Hoping it really is a tower issue and it gets fixed soon.

You can call tech support, but the home internet people will need to connect you over to the home internet technical support (where the service is not that great and is outsourced).