After having worked properly for years my Iphone 3GS is not able anymore to receive or place any call using a 3G network. My SIM card is always in research mode
Could you please tell me if my Iphone cannot place or revceive any calls in 3G mode means that the hardware is out of mode or if there is a way to repair it . I changes my SIM card two times and the Iphone is still in research mode .
Thank you
iPhone 3GS, iOS 6.1.6