I use Trados 2019 in a MacBook Pro using Parallels Desktop. It works fine for me.

But 1 week ago, after trying to deactivate Studio 2019 I got the following message: There are multiple instances of this application running. Close the other instances before deactivating the license. It was not the case. I searched everywhere in every possible way, and there were no multiple instances running.

After trying to solve the problem a couple of times by closing Trados, closing Windows, closing Parallels I would return and things would be the same. Studio opened, worked as usual, and when I tried deactivating, I got the same error message. 

The I contacted the chat and asked for the license reset. The license, then, appeared as available in my account and I have been able to use Studio in another computer since then. 

BUT, when I try to use it in my Mac (my main computer) it opens without asking for the license, I am able to open documents and even work on them, but everything is extremely slow, termbase doesn't work, it takes about 15 to 20 seconds from segment to segment, about 5 minutes to save.

I was able to unistall/reinstall. But things are still the same. No license needed, everything extremely slow. When I go to product activation, it shows the deactivate key, as if it is activated, but my license is in use in another computer. If I click the Deactivate key it shows the same "multiple instances" message. 

I'm lost here. I really need it working on my Mac, but I can't work with it as it is. 

Any solutions other than uninstall/reinstall?    

(I found this https://community.sdl.com/product-groups/translationproductivity/f/licensing/19907/deactivation-error, but the answer didn't help in my case)