Using Microsoft Edge the flow doesn’t exactly go in the order presented. I found you have to enter the key and then press Enter while the cursor is still in the key field box. Then you get the green message, then you can click on Save changes. I never see anything about the key being accepted or updated.
I was able to go back to the dashboard, updates, and install the latest pro version so it matches the free but somehow I think I went through this before and then for the next update had to re-enter the key again before the pro version would update.
I’ll try to keep track of that for next time but for now I am updated, thanks!