How to unBlacklist an iPhone 4S?

Basically I bought an iPhone 4S with broken screen for dirt cheap from a car pot sale. I got the screen replaced at a phone mender, and switched to its desired network. It showed signal for about two seconds before disappearing, I have tried everything from changing sim, restarting phone, resetting settings, etc… But still can't make or receive calls. I thus concluded its blacklisted. Is there anyway to lift this or should I just trade it in for parts?

Hi, I don't think you can unblack listed. I think the only possible way is to get it totally unlocked and unlocked to every country. Then possibly have it working other than that try apple.

You can't.once its blacklisted that's it.phones dead.kaput useless.

buy a phone that needs repairing and that's not blacklisted… And use the parts. So your money don't go to waste