Yeah this looks really flaky! I get a pop up every reboot that my license is going to expire, then I select the free, the next pop up say I am activated but still nags for the premium (and I get that), but there is no "NO THANK YOU" buttons so you have no choice but to close the popup with the "X" in the upper right corner. Next reboot? Same thing. Tried to go online to get an activation and that was a mess also.
So... hmm... uninstall and reinstall I guess, or uninstall and do not reinstall, and go with Windows Defender. I have that working on one of my Windows 10 laptops for about a year and never a virus issue (knock on wood). I forgot to install Avast free on it when I reinstalled Windows last year.
I can't remember when I started using Avast... many many years ago. Do not remember seeing a PUP-LIKE nag strategy like this before. I would pay for the software, it is that good, but I really do not need all the extra features at all. And I never felt so much like I was taking advantage of a free ride as I do now either. Time to move on I guess since I already involuntarily and unknowingly tried that route anyway.