How to get back my videos,pictures and photos alltogether

I have an iPhone XS Max and I've had it for some time now,it's in perfect condition and is a gift from a family member , that's why I came for help here cause apple support is not available in my home country and the iPhone was bought in Switzerland , about 4 weeks ago I had an issue with the phone because it went into complete shut down and wouldn't respond to any tries to turning it back on , after some time it was all good, it reset and i started working again but the only issue were the pictures, all of the photots I've had within the last 3 years are completely gone and I can't seem to recover them, they're very important pictures that I had when I first gave birth to my now 3 year old boy and I really want them back, I tried getting them back from iCloud but that doesn't seem to work either so any sort of help, recommendations are anything in general would be appreciated, much thanks .