Lumia 640 LTE - No LTE after call

[Michal Urban]

Hi,

I'm having trouble with my Lumia 640 LTE. After a phonecall my connection never returns back to LTE connection unless I reboot the phone. Airplane mode, switching data on/off, changing data connection to 2G and back - nothing helps.

Any ideas, please?

 

[TechFreak1]

LTE is only used for Data unless your carrier and phone supports VoLTE (Voice over LTE).

 

[libra89]

What carrier are you on?

Also did you set highest data connection to LTE?

 

[Michal Urban]

LTE is only used for Data unless your carrier and phone supports VoLTE (Voice over LTE).

I'm not talking about data during phonecall. I'm talking about the fact LTE is not resumed AFTER ending the phonecall.

What carrier are you on?
Also did you set highest data connection to LTE?

Yes. Otherwise I wouldn't have LTE before the phonecall ...
Im on T-Mobile Czech Republic. Brand new SIM, LTE running fine until first phonecall - after that Im stuck on E or 3G until I reboot.

 

[TechFreak1]

I'm not talking about data during phonecall. I'm talking about the fact LTE is not resumed AFTER ending the phonecall.

Maybe check your APN settings?

 

[Michal Urban]

APN setting is fine - I believe it wouldn't connect at the first place ...

Anyway, it looks like a SIM card error - I tried two other SIMs (three in total) - two older are losing connection, a brand new prepaid card works great.

Thanks for all the ideas guys!

UPDATE: I got a SIM card replacement for the original card and it didn't help. I still have three SIM cards, one works flawlessly and the other are problematic - losing signal, staying at EDGE speed etc.

UPDATE 2: I tried an O2 (another Czech connection provider) SIM card and it did exactly the same. I asked them about where the problem is and they ... voila ... adjusted some SIM LTE settings and it works. Now I'm gonna need to make TMobile do something like that too ...