Lost photos after sync with Mac

Hello,

I've changed my phone last year and I synced the photos from the old phone with my Mac, and then synced them back to the new phone. I've recently noticed that a lot of photos were lost in the process. I have checked the community post regarding lost photos and neither of those options helped me.

I've came up to the conclusion that syncing photos from an old phone to a new one is a big issue for many users, Apple has a big minus on that one.

Please help me recover my photos! Let me know what details I should provide.

Thank you!