Hi I passed on my S9 to my daughter, I had it for a year and switched to a Pixel and she had an older S7. I factory reset it and then moved her stuff in (she's special needs). I've come to find out that since I gave it to her, she cannot receive any calls. She can call out. She can send/receive texts from everybody. The house landline can call her. The rest of us get a please check number and try again. I went to AT&T store and they spent an hour with me, even changed out her SIM card. They ended up escalating the issue (tried everything). I got home and being tech support myself, I swapped her SIM card for mine, and put hers in my Pixel. I could call her number/my phone, she could call my number/her phone. No one else could call her number (so in my opinion, that takes the phone out of the equation). I swapped the cards back to their respective phones and now I could call her!! So the landline can call, I can call. Dad, and several staff cannot. Come to find out, they all (4 of them) have iPhones, 3 are on AT&T, one is on Sprint. I also asked my other kids to call her as they don't have iPhones, and alas, they cannot, so that's not it. I spent over and hour yesterday and another hour today with AT&T chat and escalated tech support. They truly have no idea. Her phone has been factory reset 4 times now, she essentially has NO apps on it as I haven't set it up again. No calls are blocked, all numbers are in her list/contacts. I am truly at a loss and so is AT&T. I've looked all over the internet, I've tried everything; cleared network cache, reset 3x, checked all settings. Any suggestions from here? AT&T could also call her but the call got rejected because it was from an unknown number. Thank you.
