Network problem in my experea E3 Duel

[n_s]

When I select GSM network I recceive Good network but 2G network while using 3G Net pack

And network gets disconected when select GSM Please solve the issue 3G ALSO NOT USFULL

[Uliwooly]

@n_s

That's probably either a faulty SIM card or even a poor network coverage

Settings > more > internet settings > accept > make sure that you have selected 3G and then 

settings > about phone > status > signal strength > what do you see?