If ownership is changing and you need to switch the primary administrator to be a different user, please have the current account owner or a user with admin privileges log in to ThunderTix and submit a support request. The request should include which user is going to become the new primary admin.
If the new owner does not yet have a user login to ThunderTix, please ensure that you create them as a new user first with "full administrative permissions" so that they are one of the other admins on the account. Then, it's a good idea to make sure the new owner has logged into ThunderTix at least once before.