Activation Code not valid?

I have installed Glasswire and uninstalled it several times always using the same Activation Code. I just bought a new computer. I installed Glasswire on it. When going to activate it, it tells me the code is not valid. How can I fix this issue?

@3jf9fab41

Please email our “activation” email address so I can help you.
https://www.glasswire.com/contact/

Hi Ken, I have the same problem here and we do not know what to do? We did have bought two codes after the first not working and the same with the second one. It keep saying that the code is invalid and I have tried everything with firewall off, etc and also I have no problem when going to the activation page, so there is nothing blocking it.

What can this be that it keep saying the code is invalid? I had bought it last year without any hassle!