Google photo backup failure
Please try the steps found on the official help page for Google Photos: My Photos aren't backing up

If it still says "backing up 1 of 119", please try to go to Settings &rarr; Apps &rarr; Photos (Google) &rarr; Storage &rarr; Clear Data. If that still doesn't work, try (from that same location) to uninstall updates by tapping on Menu (3 dots on top right) then select Uninstall app updates. If that still doesn't work, try to update the app by going to Play Store &rarr; Menu (3 lines on top right) &rarr; My apps and games &rarr; then update Google Photos App.