Sim card

[Android Question]

My phone suddenly wont recognize sim card. I Used it earlier today and it worked fine, but sometimes the network (mobile network) stopped working and came back. That means i couldnt call or anything. Now when i turn it on i have to dial my pin code as usual and unlock the phone. But still says "insert sim card". I have a LG optimus p920 3d. PLease help. I Have no idea whats happening and im not so good with android

 

[Hadron]

It's hard to say - it may be as simple as the SIM failing (they do sometimes, I've had it happen myself).

Sometimes rebooting the phone, or toggling airplane mode on and off, will bring it back to life.

Does the SIM work in another handset, and do other SIMs work in this one? That would tell you whether the problem was more likely to be the SIM or the phone.