A Microsoft file hosting and synchronization service.
Hi
I'm not a techie but think I can help. This started happening to me a few weeks ago, and it was a hassle because I like to keep everything organised in onedrive, but had to start saving files on my device because onedrive locations were grayed out.
But here's what I have figured out. I use iPad pro by the way but it's the same thing...
There are two different ways to save to one drive from your iPad or iPhone. The one that's stopped working says “save to files’ and is beneath various app icons like outlook, messages, and......onedrive! If you click the one drive icon you can save to the specific filemlocation you want. It works that way. Hope that helps