Photos taken with iPhone 11 Pro Max not appearing in iMac

Sorry, I don't know if this is an iMac or a cloud issue. The iMac is the only device having the issue, so here it goes.

I purchased an iPhone 11 Pro Max this past October. Photos I've taken on that phone appear on the phone itself and on the MacBook Pro running Catalina and my iPad.

The pictures show up when I log into iCloud.com.

They do NOT show up on the iMac running Catalina. I've logged out of the cloud then logged back in again and no pictures still, the pictures it shows in my Photos app only go to October 2019.

At the bottom of the photos app it says "Uploading 6,081 Items" <Pause>. It's been sitting there like that all morning since I've noticed this problem. I hit the Pause then Resume and it's still sitting there.

For what it's worth, this particular computer has always had issues with syncing with the cloud, particularly with music. Now it's photos.

Thanks much in advance!