Deleting iCloud backups

I recently had a problem with my phone and Mac mini. It said I needed to back up my phone before I went to the geek squad (now apples techies) So I had to buy more storage to complete the back-up. Now that storage took 23GB as I had never backed up my phone. Problems are fixed, didnt need to reinstall anything, and now I canceled my extra monthly 50 GB from apple. I am trying to delete all of the backups, but I cant find any place to do such. not under manage storage or?? All I have ever used of the cloud has been with the free 5GBs and thats all I want to get back too.