Apple iPhone 15 Plus 128GB Black (AT&T) iOS Bar – For Parts/Not Working

FOR PARTS ONLY – NO REFUND iPhone 15 Plus (black). Small crack at the bottom right, but has not spread or affect screen function. Original battery began to swell and was replaced with an iFix It battery. The phone restarts itself every few minutes. This leaves me to think there is a chip problem. AT&T phone.