Can't open project file

I tried opening the project file I was working on last night and today, I had an error saying "the file was saved using Audacity 2.1.0.0 and that I’m using Audacity 2.4.2. and that I may need to upgrade to a newer version to open my file. All my older files still open using my current version and not sure what is different with the file I made last night not to open like the rest. I saved it the same as all the other files I’ve made.

Someone please help me open my file so that I can resave it or send me where I need to go to upgrade to a newer version as it states.

The problem is caused by the (unofficial) Windows Store version of Audacity. See: https://forum.audacityteam.org/t/opening-aup-files/59478/15