My friend water damaged his LG phone from Cricket and U purchased it when I found out it worked on my AT&T Go Phone. Now I don't want to be infringing on manufactures and need to know if I can or how to reregister the LG phone Cricket sim card for my ZTE Z831 prepaid At&t Go phone.? Do I have to even though it works fine?
The model phone that is being used with the SIM card does not matter. If it works, it's fine. Although not really clear what you or him are doing. Are you saying you are using his SIM card in your AT&T phone? Or that you bought his LG phone and it works with your AT&T SIM? If you are using his SIM in your phone, that means you are using the service he paid for and are on the Cricket network not AT&T. That is not good since he paid for the service. If you are using your SIM in his phone and it's working, no need to do anything unless you want to contact AT&T and let them know of the switch for better support of the phone.