New license copied twice

I bought a new license. Copied & pasted to replace the old key but it did not work. I repeated the action & now have a message that I need to upgrade to access on multiple sites but I only have the one! How do I remove that key & start again?

Julia, as you also opened a support ticket, that we have managed already, I’m closing this one to avoid duplication. If you have any further comments please keep using the ticket.