iCloud Memory is "FULL" but shows 3.5 GB Avail.

I have a regular 1Phone 5 with the stock 5 GB of storage. For 18 months everything was fine. Very little was sent to the cloud. No retrieval has ever been attempted. Then about six months ago I got notices that nothing could be backed up as my memory had reached its capacity. Checking my phone it showed that I had 3.5 GB available. Further, more dire notices followed coupled with actions like: deleted photos were immediately deleted, as opposed to being saved for a period of time. Out of desperation, I chose to delete my entire iCloud content. I was only for back up. Since I had backed up items to my computer, I did not care. Then new warning started that in 20 days, 15 days, 10 days, etc. everything in my iClould account would be deleted. Each of these warnings was accompanied by offers to buy more storage space. The time came and went. I assumed my iCloud acct was empty.

Now, I can see recently deleted photos. But, I am getting new warnings that I have run out of storage space and I should buy more! I checked my Settings>iCloud>Storage and it still shows 3.5 GB Available. The same iPhone amount as it was 2 years ago.

Any help would be appreciated.