when i insert it it says sim registration failure
i cant even call it says emergency calls only
WHAT DO I DO
10 POINTS FOR THE ANSWER THAT ACTUALLY WORKS
i think it was pay as you go i just inserted it in 1 hour ago
Some of the reasons sim card not working in your mobile
1.Bad SIM -if it wasn't unlocked you'd get a message asking you to enter a PIN.Get the pin from an online vendor like ClassicUnlocking.com .
2.With a warning that you have 10 attempts to enter the correct PIN code or it could be locked forever ,if you don't get that message it's "mostly likely" unlocked.BUT find a phone with a known working SIM and see if it will work and connect to the network.
3.May be a hardware problem try flashing with a custom rom.
4..This has to be a problem with the SIM card slot, which is soldered down to the logic board. It's possible that it's a mechanical problem , you might be able to open it up and discover that the card-detect switch is failing to detect SIM card insertion.
5.The os system has been updated and your phone is not being recognized with the right settings , this happened after a update a year or two ago .