when my iPhone15 pro max upgrade to iOS18.1.1，it can not connect to hotPot of my lot device(os android5.1) any more and my iPhone12(iOS 18.1.1) has no issues.
Both the 15 pro max and the iPhone12 works well with another device (OS android 10.0).
had tried:
1.Forget Network (and re-add your desired Wifi network),
2.Reset Network Settings (under Settings/General/Transfer or Reset iPhone)
3.Turn Airplane Mode On then Off after a few seconds
4.Restart the iPhone.
5.Rest all setting
6.Disable VPN
7.close the the settings from rotating my WiFi address
Did anyone have similar issues?