iPhone’s issues

Ngân99,

Thank you for clarifying that this isn’t the iPhone with the water damage. Were you able to look at the article about unexpected restarting on your device?

Here it is again: If your iOS device restarts or displays the Apple logo or a spinning gear unexpectedly - Apple Support

Do you see a spinning gear or an Apple logo just before it restarts?

All our best.

Hi, Ngân99.

Thank you for reaching out on the Apple Support Communities. If we understand correctly, your iPhone restarts frequently. Is this the iPhone XS Max that received water damage in this post? 

My phone got water damage and when I reset my phone, it just turned off a few minutes later - Apple Community

If it is, the suggestions by our fellow Apple Support Communities users are all good advice. You’ll want to reach out to Apple Support for service options.

Contact Apple Support

If this is happening on another device, see if this article helps:

If your iOS device restarts or displays the Apple logo or a spinning gear unexpectedly - Apple Support

Cheers.