Any help here would be great!

My iphone 3g is on 4.1 jailbroken with redsn0w and unlocked with the 6.15.00 baseband. It can successfully unlock and get service, but when i sync with itunes, it drops to no service right away. I have tried both setup as new iphone, and restore from a backup. If there is a way to restore from backup it would be great because i have lots of important texts i dont want to lose. I have iphone backup extractor, so i can read them, but its not the same.

Any insight would be greatly appreciated