iCloud Photo Library stuck uploading on iPhone

I recently activated iCloud Photo Library on both my iPhone and Mac. The Mac has uploaded all the photos and is up to date, but my Iphone has 614 photos that are waiting to upload and has been for more than a week now. It's stuck, nothing happens.

I've tried leaving the photos app open over night .

When I go to Photos in Settings the blue bar is stuck at one third.

What should I do?