iPhone does not change time automatically.
I paste a post below from another user in 2018. Like him or her and the 331 other users who selected “me too”, I have the same exact problem in the same exact location, going from EST to CST, time changes, and, coming back from CST to EST, it does not. Overslept an hour the next morning because forgot to manually force it to change. I.e., it’s now about 10 hours later, and, it still hasn’t changed the time back to Eastern time zone. The problem is repeatable and recurring apparently happens on different model iPhones. The previous user already received all the standard replies about checking all the time and date settings, tried that and it doesn’t work. This is an Apple IOS problem!
“I have an iPhone X and my wife has an iPhone 8 Plus. We live in Tallahassee (EST) and travel quite frequently to our daughter's home in Crestview (CST). When we drive TO Crestview our phones switch time automatically as they should. However, when we come back to Tallahassee they do not switch back to EST. We have tried all possible settings in the phones and nothing works unless we MANUALLY change them back after arriving home in Tallahassee. Is there a solution to where we don't have to do this manually each & every time we make this drive (several times per month)?”
iPhone 8