I have this problem, too. Spending so much time at home, I didn't realize I was not getting the 5G indicator till early Feb when my brother got an S21. I have looked back and can see that I lost the 5G indicator on my S20 (on T-Mobile) between Dec 6 and Dec 10. I am sure that coincides with when I received/updated to Android 11. Now the only way I can get the 5G indicator is by forcing the phone to use 5G band N71 via NetMonster's access to the Network Settings hidden menu.
It is not just the indicator that is missing. When I first got the phone in October I was getting 150 to 270 Mbps download speeds. Now, no matter what I do, the best I get is 80 Mbps. My wife and daughter also got S21s and they sit right next to me and get 260 to 300 Mbps. They are not on mmWave either.
When I use NetMonster's Network Settings menu to select 5G band n71 it does connect and indicate 5G. Then, when I switch back to automatic, I can watch as the phone steps back down over about 60 seconds to 3G/4G as follows:
5G NR 600 with ARFCN 125330 (Status bar shows 5G)
4G + 5G LTE 600 with ARFCN 125330 (Status bar shows 5G)
4G + 5G LTE 1900 with EARFCN 825 (It reports this as NSA where the others don't say) (Status bar shows 5G)
4G LTE 1900 with EARFCN 825 (Status bar shows 4G)
3G UMTS 1900 with UARFCN 9838 (Status bar shows 4G)
At this point I do not get good Speedtest performance.
This makes it appear that the phone software is making a choice to not remain connected to 5G.
Honestly T mobile says they have Nation wide 5G, well I'm here to tell you they don't !. At best it is spotty here where I live, but as I get closer to down town then I get it. And I'm only 3 miles away from downtown.
I believe my T-Mobile Galaxy S20 5G phone has lost its ability to make VOLTE calls! This likely occurred with the Android 11 update in early December which coincides with the last time I had a great speedtest and the last time I consistently saw 5G on my status bar.
I have determined that the phone will rarely choose 5G when a GSM band has been selected (or is available??). Looking further I have used the hidden Network Settings menu (made easy to get to via NetMonster) to select specific bands. If I select LTE b2, b4, b12, b41, b66, and b71 along with NR b41 and b71 the phone will connect to 5g (and probably aggregate a bunch of channels) to give me download speeds of 290 Mbps. If I attempt to make a phone call with these settings the call hits the network and ends immediately (no dial tone, no ringing - it drops within a second.) If I add to the above bands the GSM band 1900, it will allow me to make phone calls but the connection speed drops to 38 Mbps.
Thus, if I don't have a GSM band selected it won't make phone calls (VOLTE not working). If I do have a GSM band selected it gives me poor connections.
RESOLVED by a "Factory data reset". It seems my inability to use 5G data on my Galaxy S20 while also being able to make and receive phone calls (using VOLTE) was due to some corruption of data that a factory data reset was able to resolve.
It is disappointing that something on the user data side of the phone can cause it to refuse to remain in IMS 'Registered' status and nobody was able to diagnose this problem. I am convinced other S20 owners are experiencing this same problem and are unaware of it. I went 2 months before I noticed it (December and January) and then spent another month and a half diagnosing the problem and burning through probably 2GB of data doing speed tests. There must be a better way to assist customers. I spoke to T-mobile 3 or 4 times on the phone and visited T-mobile stores 3 or 4 times and spoke with a Samsung representative at Best-Buy and with a representative at U Break I Fix. No answers. They narrowed my problem down, though but if I were not an IT professional I would have ended up exchanging the phone under warranty (hopefully).
Here is an easier to recognize symptom of this particular problem. Go to Settings (pull down from the top of your phone screen and tap the gear icon in the top right), Scroll to the bottom and tap About phone, Tap Status information, Tap SIM card Status. The result for my phone when experiencing this problem will be the following:
Status bar - will show 4G (if your wi-fi is turned off. You want this to show 5G as often as possible when you are within reach of a 5G tower) Network - T-Mobile Mobile network state - Disconnected (this is ok because you may have your wi-fi turned on. If you turn wi-fi off you should quickly see it switch to Connected whether you are having the problem or not) Service state - In service IMS registration status - Not registered (I believe this is probably the Key. They say that if IMS status is not registered then the phone can't do VOLTE, which is required in order to do 5G data along with phone calls.) Signal strength - '-78 dBm 42 asu' is what mine showed at one point. (Signal strength will vary and is not a cause of this issue. I am located 1/8 of a mile from a strong T-Mobile tower that serves all signals from 2G, 3G, 4G LTE, and 5G NR. Even the T-Mobile technicians told me I was close to a 5G tower.) Mobile voice network type - UMTS (It SHOULD say LTE. This is a key symptom as well - telling you that you are not able to make calls over LTE. 5G phones should always say LTE, here, unless there is no LTE signal - in which case, T-Mobile will serve yuo on a 3G or 2G network that, hopefully, is available.) Mobile data network type - UMTS (It SHOULD show NR SA or NR NSA. This is a key symptom of course - You bought the S20 because you wanted to use 5G. You may see LTE or something less if the tower you are connected to does not serve 5G.) Roaming - Not roaming
The factory data reset was also frustrating. I have an old Galaxy S8 and I used Smart Switch to 'replicate' my S20 on the S8. This was effective except that it did not bring game scores over from the old phone - which is a big problem. I ended up using Helium to back up my apps (particularly my Angry Birds and Solitaire games). Then I restored them on the S8 and I got the scores. Now the S8 is pretty much exactly the same as the S20 (I didn't bother logging into all the apps, but I was confident I could log into my banking apps and such.) Once I did the Factory data reset on the S20 (I removed my SD card before I did the reset, just to be safe), I used Smart Switch to copy the apps and data back to the S20 from the S8. This worked very well - it even got the game scores. I didn't have to use Helium to restore the games.
I'll note that when using a USB cable with Smart Switch does the data transfer of several GB of data in 10 minutes or so, which is awesome. But it takes about an hour to install 200 apps and you have to wait all that time before you can see if you got your game scores.
Just to clarify did you have a 5G sim card on your 5G phone? It is very important to get that 5G sim card because Tmobile is deploying 5G Standalone and you only get that signal if you have 5G sim card.
Thanks for asking. Yes. I replaced the SIM card twice. My original was an r15. (Troubleshooting on my own, I swapped my SIM into my wife's S21 and her s21 continued to show a good 5G connection. I put her r15 SIM into my phone and I got the problem connection immediately.) I replaced my original SIM with a new r15 with a T-Mobile tech over the phone (I had one from my wife's purchase of an S21 in early Feb 2021.) Then a T-Mo tech the following week recommended I take the phone to a T-Mo store where I had the SIM replaced by an in- store tech. They were baffled while my phone went right back to the problem behavior.
So in the end, I have a brand new SIM from T-Mo (from 3/21/21 visit to the T-Mo store) which does not resolve the problem. Tuesday 3/23 and Weds 3/24 I did the factory data reset and that resolved my problem.
I had been worried that the reset would put my phone back on its original Android 10 where I would have to perform upgrades to get it back to Android 11, but to my surprise, the factory data reset leaves the operating system the way it is - at Android 11 with the One UI version 3.1 in tact. So now I am a bit more puzzled since the factory data reset doesn't uninstall anything on the operating system side of the phone. The only thing that changed is that my personal data and apps were uninstalled/deleted. And all the apps got reinstalled with the exception of OneDrive, Samsung Pay, T-Mobile app, and Calculator. I have reinstalled them and still no problems. I have the correct connections displayed in Sim Card Status (VOLTE and IMS Registration is 'registered' while Data connection shows NR NSA.)
@TojoTS Your line on tmobile may be on de-prioritization thats why you get slower speed. Now, what happen after you factory reset the phone did you get same result no 5G?
I get 5G now. The status bar shows 5G when I am not on wifi (when I am in 5G coverage area). The SIM card status shows as it should, also - Voice Over LTE, and Data over NR NSA, and IMS Registration status is Registered. After trying so many other things, the factory data reset is what fixed it.
