iPhone shows erratic behavior
A couple of weeks ago my iPhone was giving a message that the SIM card was not installed, every time I took it out put it back in it recognized the SIM card after while repeated the same error message. After a couple of days it stopped giving this error. Now there is a erratic behavior of apps opening and I lose total control if the phone, and it becomes very warm. I have to disconnect from WiFi, power off and restart to get it back operational. This all started after receiving a message that my Windows computer was hacked, and I lost all my 2020 files saved on iCloud, I noticed that their was no synchronization on the iCloud, first I thought it could be a Windows issue, again I lost the iCloud files after receiving the hackers email. I installed TotalAV on the Windows computer and IPhone both shows to be clean. It's only the iPhone continues with this erratic behavior. Any advice
iPhone X, iOS 15