I have 5 authorized computers and both devices are dissassociated

I read an article trying to learn why iTunes was deleting my music because it said i can only have one iTunes and already have 5 devices authorized or something to that effect. So I had to read up on it, found out about I should've deauthorized my computers before I sold them, I'm down to just one laptop. Yet, 5 authorizations. Then it says look to see how many devices are associated. I found my iPhone was dissociated but iPad was not, so I went and associated the iPad. When I tried to back up the iPad, got the same message with it, you can only use one iTunes account, etc so I had to stop the backup before it erased my music on that one as well. Things went from bad to worse when I had to do a Windows 10 reload, now both of them are disassociated, and no way of my being able to backup to iTunes, so what do I do now?