My 3g iphone sometimes says NO SERVICE or NO SIM

[Vegan TJ]

anyone else have this problem i usually just turn of then turn back on and its fine but i dont want these problems to keep happening...oh and were i live i always have service

 

[nickspohn]

anyone else have this problem i usually just turn of then turn back on and its fine but i dont want these problems to keep happening...oh and were i live i always have service

Try doing a restore in iTunes.

 

[Auzburner]

You may also have a loose SIM card. You could try putting that new tool to work and check.