How to annul 2 month trial?

hello I am trying to annul my 2 months trial version avast premium for pc.
For buy 2 months trial version i used only credit card.I dont used e mail for buying 2 months trial version.Helpdesk avast doesnt help me. what can i do?
sorry for my english :slight_smile:

→ https://support.avast.com/en-ww/article/Order-Subscription-FAQ/