Can´t deactivate and activate my license

I needed to uninstall and install again Trados Studio 2019 on my computer (Windows 10), and need to re-activate my license. But any time I try to deactivate it first (from my account AND from Trados Studio, both online and offline deactivation modes, I get the message "an error occured". 

How can I deactivate and activate my license again? 

Thanks

Sarah