How to insert licens-key?

I have now installed v5 and am looking for the right place to enter my license key from v4.
Where can I enter my license key in v5?

Found the place in account management now but get an error when I enter my license:
“400: The “white label” license is not valid”.

Was the license purchased within the past year?

Please email the license to and we can check it for you.

I don’t know why, but after several attempts the key was accepted.

Ticket can be closed.