iPhone 12 stuck of step 3 of 7 steps and not syncing photos

My iPhone 12 Pro Max iOS 17.2.1 and MacBook Air Sonoma 14.1.2 90 GB of 498 GB available.

Phone backs up to MacBook but no longer syncs to photos.

In finder it gets to step 3 of 7 of syncing then stalls on preparing to sync.

Have updated and reset both devices. Cleared cache old storage files etc.

I have been trying multiple times over the last few weeks and following suggestions from earlier posts. Nothing seems to work.