I just realized that the title of this thread says "when the license is expired". My previous response is applicable if you had a permanent license.
If your license was expired, then it means that you have never activated it to become a permanent license. You may go to the Micro Focus product licensing page to activate your license. Please take note that you can only activate your license once. If the license was activated previously, then you will need to deactivate (or revoke) the license first, and then you will need the revoke key as a proof before you can activate the license from a different machine.