There is no such issue. Tempered Glass is only a glass screen protector, it will not cause any software or hardware issues

I can say it is impossible for the glass sp to cause such problems bcos tempered glass screen protectors are made from glass, not metal. It will not in any way interfere with the reception or cellular network. Even cap ayam RM10 pasar malam tempered glass will not cause such problems. Mayb ngam ngam it so happens that your wifi module in your iphone got problem when u install the glass sp