iPhone not synching with photos app on MacBook Pro

That's weird. It sounds like the problem is with the MacBook, not the iPhone or iCloud.

To narrow things down, try these steps:

• Restart the computer (of course)
• Re-start in Safe Mode. This bypasses certain potentially disruptive processes, and it often helps. Safe Mode is different for different computers, so see this: 

           Start up your Mac in safe mode - Apple Support 

Let us know what happens…

Did you enable iCloud Photos in Photos on the MacBook Pro?

What version of Photos is running on the MacBook Pro?

What status shows at the bottom of the All Photos view below the counts of photos and videos? Is it "Synced with iCloud Just Now" or something else?

You can't stay in Safe Mode-- it's limiting in what you can do. So, back to normal. Often that is all it takes. If that works, then all is great.

If you still have problems, then the first thing to check is Login Items (in System Settings.) I have no login items, and that's the perfect number.

Yes Me too