To submit a technical support question please go to the Proxmox Customer Portal at https://my.proxmox.com and submit your question there.
If you are a first time user you have to register and create a new user account first. After registration and login, go to your profile page and update your organization's details like for example company name, address, etc..
Note: The field 'Subscription Key(s)' cannot be edited.
As soon as you have ordered and paid your subscription, you can submit your first support ticket.