iPhone deleted my photos by itself!
Everything was normal until I see that 4/5 of my photos were gone. I did not do anything. How do I gain those photos back? Some of them were really important and that’s why I’m here.
iPhone 6, iOS 12
look here Get help with missing photos - Apple Support
and if you weren't syncing them to icloud you can do this Restore your iPhone, iPad, or iPod touch from a backup - Apple Support