Avg no longer on pc

I purchased a one device three year subscription for my pc.
Since then, the pc that the software was on has been formatted and the hard drive replaced. I cannot therefore cancel the subscription on that PC.
I have installed, successfully, AVG Ultimate on my new PC and now AVG tells me I have one too many devices on the license.
I cannot find on my account or anywhere else how to cancel the subscription on the first, "non-existent" system so that I can use it on my new PC.
Do I have to bite the bullet and take out another subscription?

Hello Keith,

You've reached the AVG community support forum.
We apologize for the inconvenience. We'll certainly look into this and help you.
Before we proceed, we'd like to inform you that we couln't locate any active AVG subscriptions under the email address you've used to contact us here.
As we need to locate your subscription in order to troubleshoot your issue, we've sent you an email requesting further details that will help us locate your subscription. Please check your inbox/spam folders to find the email and use it to get back to us.

Hello Keith,

You've reached the AVG community support forum.
We apologize for the inconvenience. We'll certainly look into this and help you.
Before we proceed, we'd like to inform you that we couln't locate any active AVG subscriptions under the email address you've used to contact us here.
As we need to locate your subscription in order to troubleshoot your issue, we've sent you an email requesting further details that will help us locate your subscription. Please check your inbox/spam folders to find the email and use it to get back to us.