My iPhone 8 won't sync photos to my laptop

So, I have an iPhone 8, I've had it for a couple of years now and I'm having trouble syncing the photos on it to my MacBook Air. I used to be able to just plug my phone into the laptop and be able to sync the photos within a couple minutes. Now however, whenever I plug in my phone to sync photos to my computer, only a small amount of the newer photos will sync, and even then sometimes I have to open the photos through my phone in order for even a few pictures to be able to sync. Usually it's also photos that I took within a couple of days and nothing older (like photos taken within the past months). I want to make sure that all of my pictures sync up before I update my phone. How do I fix this?

note: I tried switching ports, and that worked for awhile, but it's not working very well anymore.