How to cancel Avast payment?

Avast Free Antivirus / Premium Security
1

I have Avast Premium, but I invited a friend and gained free Premium for 6 months. So, I want to cancel Avast payment. I have to pay it after 11 days, how to cancel it?

2

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

3

I can’t see unsubscribe option.

https://media.discordapp.net/attachments/771915033281167363/835788405161590794/unknown.png

4

→ https://support.avast.com/en-ww/article/136/

5

I’ll try but I get a e-mail from Avast and they said “payment is unsuccessful”. Is it a loan or I need to pay it?
I cancelled repayment but I’m wondering.