Microsoft on-premises server product that runs Office Online.
I got the message today when trying to set up a new MS 365 Dev account. My previous one had expired a year ago. As some others here have reported, going into my account and just changing some the checkboxes about what tech I use was enough to "fix" it. I suspect it helped that I added Microsoft Graph to the list of products of interest. Anyway, give that a go before you abandon hope, though it may not work in every case.