SIM Problems

[shocky13]

Hi, I just went ahead with putting on a new red OEM screen and back plate for my IP4. I took my time and followed a guide very carefully. But this is my only problem: no service. I had to take out the sim card to remove the logic board, and when the phone was complete and ready, I put the card back in. Ever since then I have been getting no service. Any help is appreciated, thanks. (If you plan on responding to this thread saying get a new phone, please don't respond)