iCloud 'backup' shows full but phone shows 0GB used

I have 5G of storage on my iPhone 7 (11.3). Sometimes I clean the backup by deleting it and then backing up again. This gets rid of the incrementals and therefore less storage is used. Today, I did that while on DND (if that matters) and the backup summary shows 3.4 of 5G uses which is 1.9 photos and 1.6 Backups.. However, when I click into the "backups" choice it says 0 KB used... How do I fix this because I can not longer backup due to the phantom space showing used. I suspect a syncing issue where the icloud never received the instruction to delete the backup (1.9G).