I received the confirmation email saying that my license is deactivated but I still can't activate it on my new computer. Why?
When you activate a license, it will be tied to the computer and the user account that made the activation.
Thus, multiple activations from the same machine but different user account is possible.
As a consequence, if you would like to use your license on a different machine, you will have to deactivate your license from all the user accounts where the license has been activated on.
It's only when you've completed all deactivation requests you will be able to activate your license on the new computer.
For more information, see “License management” under “Installation” section in NeoLoad documentation.