iCloud Photos disappeared from devices and iCloud.com

vathana70 wrote:

I synced my photos to iCloud, but suddenly they disappeared from both my devices and iCloud.com.

Read here Set up and use iCloud Photos - Apple Support

and here If you're missing photos or videos in the Photos app - Apple Support (IE)

All your pictures disappeared? Are you absolutely sure that you are looking at the same account? This is certainly what would happen if you accidentally connected to a different account.