iMovie won't downgrade
Thanks to Catalina causing a number of problems, I had to downgrade for my old MacBook Pro. So I was recommended to go back a couple upgrades and using Sierra. Now my iMovie won't work. I tried to downgrade by upgrading in the App Store. I had to update my billing info but now it does nothing. I click on iMovie. Under the purple star icon it has a button that says Upgrade (which worked until I updated my billing info) but now the timer keeps circling and it does nothing. So, is there any other way to downgrade my iMovie? BTW, after being a Mac user for 13 years, I am finally fed up because of all this hassle.
MacBook Pro 13″, macOS 10.12