How to cancel 60 day trial?

Hello. I’ve activated 60 days trial on my PC without an account, through the software. Now I want to cancel it just because I don’t like subcriptions charging me without my second confirmation. I want to rethink about it then decide if I’m going to buy it. What am I supposed to cancel free trial?

Edit: So I found this article: https://support.avast.com/en-ww/article/126/
I’ve done it and I wonder if I need to do something else. My free trial won’t be renewed, right?

If you’ve cancelled it, no.
All that’s left to do is uninstall the paid trial version.
You should be offered the option to convert it to the free version.