If your license key has this format XXXXX-XXXXX-XXXXX-XXXXX, follow these steps:
If you do not have a license key or cannot locate your order confirmation email, go to the Malwarebytes website to buy a Premium subscription or see how to find your Premium license key. Your license key is located in the order confirmation email that was sent to you when you purchased your Premium subscription.
To activate your Malwarebytes subscription, you must have a license key purchased from the Malwarebytes website.