AT&T Samsung S3 won't receive 3G, 4G on Cincinnati Bell network. Bell is a GSM network. I purchased an unlock code for the phone because AT&T said it could take 10 days to receive an unlock code from them. The unlock codes are different. Is it possible that the AT&T code would open up the software for use on another network, or is this a hardware issue? Bell says APN settings are correct. Is there a mod or software fix? Would using the AT&T unlock code fix this issue?