I have Studio 2021 and 2019 both with extra actiivations, and my 2021 licence specifically says "allow Studio 2019", yet my second computer won't accept the only visible activation code in "MyAccount".

I have two computers. 2021 is activated on both. The problem is 2019. It is activated on one computer but "product Activation" refuses to accept the code visible in MyAccount for my second computer.

It wasn't easy to find the "reset licence" page, but that shows two activations for Studio 2019, but almost everything there is blacked out.so I don't know which one to reset. I am extremely wary of resetting both in case I lose my already activated one.

I should have a ticket number SD-56617 but I also received a mail with the same date and time claiming that "closed cases cannot be updated" You cannot win on this one. A new mail with no case number in the subject or replying to one that does almost always result in "visit website" mails.