I have the Iphone Xr through ATT which is a carrier that has cellular network updates along with the ios updates. Since i turned on my phone from the update, my service has not been working one bit. While away at college in a more rural area with less cell towers my phone connects and then drop service frequently. I have tried almost everything especially troubleshooting with apple support on the phone. AFTER a month of getting sent back and forth between ATT and apple, an apple senior advisor ran a diagnostic with the issue occuring during the diagnostic and they detected a hardware problem. They told me to bring in my phone to the nearest apple store to get this issue resolved. This apple store was in a big city where there were many cell towers obviously, and my phone had no service issues at all, so when apple scanned the device, they could not detect the cellular problem and they would not give me a new device and told me to go back to my carrier. After going back to my carrier, they discussed with me that an apple rep had contacted them and told them that the new IOS 14 had deleted the APN settings off of the iphone with the update and this caused the phone to not reach service in areas with less cell towers, or something along those lines. The specific carrier store i went to had over 50-100 people in that week with the same issue, especially the iphone xr's. I contacted apple again and they took in my phone by mail to repair, and put a priority on it for them to replace my phone basically no matter if there was an issue found, since the senior engineers had found an issue in the first place. WELL apple only decided to replace my battery and some other issue with wired charging AND sent back the same exact phone. I STILL had the issue. I called apple back the second i realized this and they told me to try a new sim even though i knew this would not work. Went back to carrier to get the new sim and they told me to just change my data from LTE to 4G and so I continued to do this and i have had a stable connection. contacted apple again just now and was responded to with a very rude senior advisor. He said for me to just send it in again but i do not have the time for that, especially if they're going to find no issues AGAIN. I repeatedly told the advisor about this forum with hundreds of people having this issue and what the carrier had told me but he did not address this and almost like he couldnt address it for some reason. he continued to tell me "it was just the area" after i told him multiple times it was not working in other areas across the state. I am angry and apple need to stop hiding this issue and find a fix!