I am having trouble syncing the photos on my iPad Pro, iPhone 7 and my Mac...is there a fix for this?

I am having trouble syncing the photos on my iPad Pro, iPhone 7 and my Mac...is there a fix for this? My iPad keeps saying that it is 'Uploading 34 photos' but it never actually uploads them. And there are photos I took on my iPhone that won't download to my iPad. I think the problem might be that i don't have High Sierra on my Mac yet and won't upgrade that until they get the new files system set up for non-solid state hard drives. Is there a fix without restoring the iPad?