Cricket 530 wont work with ATT Sim

[Big Papa Smurf]

So I got a 530 as a back up for my phone. I wanted to use it to test W10TP but since it wont install its sitting in a drawer. Now when I needed to use it. It says I need an unlock code. I called cricket. They said I have to contact the person I got the phone from. Said person never responds.
If I put in a cricket SIM, it works fine. But then I try to put my ATT SIM. It asks for a code.
Who am I supposed to contact to unlock the phone for ATT? Can I purchase a code from somewhere? I didn't think I'd need a code since I'm already on ATT...

 

[Zachary Boddy]

Your phone is locked to Cricket. If you had bought a phone from AT&T, it would be locked to them. You have to contact the carrier your purchased your phone from and request an unlock code. As far as I know the only way to get one is from the carrier your purchased the phone from.

 

[oviedofreak82]

Actually, you can take an AT&T locked phone and put a Cricket SIM in, not the other way around as you said. Was able to do this with a Lumia 920.

 

[Big Papa Smurf]

Yeah. They keep saying I have to activate service for 6 months. I'll just let my brother have it. Live and learn.