Licence key Activation not working

I have uninstalled comodo antivirus and firewall from one of my machines and trying to use the license on my new machine but am receiving an invalid licence key.

Getting a error 12 which geek buddies tell me is an account issue which means the key has already been used by another machine for comodo antivirus.

I need the account reset to allow me to continue to use my license on my new machine. I have contact accounts (“” <>) department multiple times since start of January without a response.

Can someone help me?