Some photos from iCloud Photos after backup mysteriously disappeared...

Hello!

I bought an iPhone XS a month ago. On my old iPhone I made an iCloud Backup, then I deleted everything and gave my old iPhone to my mom (i don't use that phone anymore).

After checking in iCloud Photos on my Mac it was really like that - absolutely every photo was on. On my new iPhone XS I chose the option "Restore from iCloud", all apps were restored, but unfortunately not all photos and videos. I noticed this a few weeks later when I was looking for something. I was shocked that they were not downloaded from iCloud Backup (or uploaded at all). 30-40 files (videos and photos) were not restored in a mysterious way. I tried repeatedly to restore them somehow, but I failed.

I didn't delete them, they just disappeared mysteriously after I backed up to iCloud. I tried repeatedly... Please tell me how to recover those 30-40 files that have disappeared ... (e.g. IMG_0058.HEIC and the next photo is IMG_0080.HEIC, IMG_0088.HEIC..????) I am very surprised because I made an iCloud backup and it was successful. However, after downloading the files from iCloud Backup, some were missing. These 30-40 photos are also not available on iCloud Photos on Mac now. I do not know why. I am very sad because these were photos and videos from a long-awaited concert.

And please don't tell me I deleted them. I was at a concert of world-famous star, for which I paid a lot of money. The shots have emotional value for me. Can I see the iCloud Photos upload history somehow? Please help me.

I am very angry and sad...