iPhone 13 Po - Freezing and then restarting

I'm facing this issue on my iPhone since today, my iPhone freezes and then suddenly restart after few minutes. I also keep on getting the iCloud message regarding that it may charge me, and FaceTime and iMessage my charge me is also appearing (I have an e-sim and i keep on traveling back and forth). Not sure if both are relatable but I'm just screening my problems.

I need to also backup my iPhone (78Gbs) and as soon as it reached half way the freezing issue happens again and restarts all over, which is frustrating and i'm kind of worried about my data.

Updated my iPhone today to 16.3.1 hoping this could solve the issue but it persists.

Did anyone face this issue ? If yes, how did you solve it?