IPhone 3GS 6.15.00bb on 4.3.3 has no service.

[Usafhester08]

I have no idea how to fix this issue, I have used all methods that i know on to work on this.
It searches for my network, then flips to no service.
I jailbroke it with redsn0w and unlocked it with ultrasn0w. I am lost at this point when i jailbroke it and unlocked it originally it worked for about 4 hours then it just quit.
could anyone help me pleasee??????????