iCloud photos not syncing

My photos from my iPhone had been sync'd to iCloud till early May 15. Not I can't see my new photos taken from my iPhone on iCloud photo website or Photos app on my macbook. My iCloud photos just stopped syncing.

I think it may be related to my trip to Hawaii staring from May 16th. But I have been back to town for more than a week and still no new photos from my iPhone are uploaded to iCloud.

Tried to turn off and on the iCloud photo on my iPhone. It didn't work.