Hi, thanks for the instructions on how to verify I have the most recent version of an app. I tried that and discovered that Excel needed updating. I updated Excel and still got the "Activate Microsoft 365" message, so just to be doubly sure I uninstalled and reinstalled Excel again. Still got the message.
You mentioned screen size. I assure you, my iPad Mini's screen size is less than 10.1 inches. I've measured it with a tape measure myself, but just for confirmation I went to Apple's site and got the hardware specs, which are here:
https://support.apple.com/en-us/121456
It lists the height as 7.69 inches and the width as 5.3 inches. I then used the Pythagorean theorem to determine that the diagonal measurement is 9.34 inches.
So, what's going on? One thought I had is, this iPad Mini A17 Pro has only been sold since last October, so it's relatively new. Maybe Microsoft hasn't been informed yet that it's less than 10.1 inches? If this isn't the answer, can you think of anything else that might be the issue? What else can I do?