unlock not working after iphone was restarted

[fjaff]

I have an Iphone 3g, it was working perfectly after jailbreaking it with Spirit, then using ultrasn0w 0.93 to unlock. I could make calls, send texts etc. Then I turned the phone off, when I turned it back on, all the signal bars were gone, so I cant make or receive calls anymore. Anyone know why that happened? This is frustrating.

Firmware: 3.1.3
Baseband: 5.12.01
Bootloader: 06.04

I used 2 Orange sim cards that work on other phones.

Please can someone help me?

[tekwiz]

try reset network settings?

[fjaff]

I tried that but still doesnt work. The carrier Orange shows in the top left but no signal bars at all. Crap.