IPhone XS 256GB order AT&T

Product Name: IPhone XS 256GB order AT&T
Up for sale is an iPhone XS with loads of storage. The phone is paid off, but locked to AT&T. Clean IMEI and order ready for someone to put it to use. The SIM card slot is very on and off. Sometimes it will read the SIM card and sometimes it won't. I do not know what could be causing this. Every single other thing about this phone works as intended. Battery life is at 82%. Comes with original box as pictured. Phone is extremely clean with little to no scratches. Nothing on the phone has ever been fixed or replaced.