JB-Mavic Pro

Recently acquired a working Mavic Pro from my brother. He had a wire break on camera so I bought OEM replacement entire unit on stabilizer just plug the wire into harness on board and attach the front vision sensors etc.. basic easy.. It flew great prior to this at his house with weak gps signal error occurring occassionally but flew it great no crashes. Once I brought it home I replaced the gps module because a wire was broke off. After that I plugged it into the computer and dj assistant app to calibrate entire camera system, said firmware needed updated which was successful, also calibrated compass and imu successfully. First was stuck in ATTI mode, will not access any gps signals, and have final check redundancy... I have done everything I could find on here what am I missing. Immediately says wont take off in top left in red and that repeated error. Gps module I replaced bad? Need to downgrade firmware? PLEASE HELP