Lightroom 6 Serial number issue

Hi, I have just had to reinstall Lightroon 6 onto my new computer, but get a message saying "the serial number you entered has been revoked". I have rechecked my number, and contacted Adobe support but they are useless and cant give me an answer. ANybody able to help????

Thansk,

Steve

{Moved from Lightroom Cloud to Lightroom Classic Forum by Moderator}