Inserted AT&T and T-Mobile SIM and it only recognizes 2G networks.
What city do you live in?
You were never going to TMobile HSPA. They're only on AWS 1700/2100 and they're reframing 1900mhz.
The only reason you wouldn't get AT&T HSPA is if you're in a city where AT&T doesn't have a 850mhz license. Those do exist, so I'm just wondering which market you're in.