Android doesnt connect when mobile data is turned on

[wsl543]

Hi
This happens under android 5.1
When I hit mobile data nothing happens.
I have to launch airplane mode and turn it off.
Phone is back online and then it connects properly.
What's going on ?

 

[B. Diddy]

Welcome to Android Central! Which phone? How are you toggling mobile data--using the Quick Settings toggle (when you swipe down the notification panel), a 3rd party mobile data widget, or the main switch in the system settings?

 

[wsl543]

phone model: zte a452
i use quick settings toggle,
main switch in system settings behaves the same - doesnt turn the connection on

I also use 2G only, maybe there is something ?

 

[B. Diddy]

What do you mean that you use 2G only--does your wireless plan include 3G/4G mobile data? Or are you stuck on 2G? Go to Settings>Mobile Networks>Preferred Network Type​, and make sure it isn't limited to 2G only.