Not syncing with the cloud

See these articles https://support.apple.com/en-bw/HT205754

https://support.apple.com/en-in/HT203521

Try going to iCloud.com using a computer to see if the items are there and which device they are from. That should show which device  isn't syncing. On the device that isn't syncing, go to Settings/Your Name/iCloud and disable syncing. After a couple of minutes, turn syncing on. Allow time for the sync to complete. As a last resort, you can also try signing out of iCloud and then sign in again.