Google Docs not saving my content?

I'll type for less than a minute before it starts to autosave, but it'll interrupt me with the error message, "can't save changes because you can't create files using this account. To avoid losing work, copy any changes you've made."

I'm using my personal email for google docs and it's worked perfectly fine up until this point. I only wanted to write down novel ideas.

It does seem to save the work despite the error message, but it stops me from typing every time it comes up.

Just so you know, I am also using my android phone. It's a Galaxy Grand Prime. I have also previously logged into my hangouts account while simultaneously logged into my school account (which is not a private email), but it's never caused any problems in the past.

Does anyone know what the problem is? Google wasn't helpful. Thank you!