I got charged by DRI*Avast Software even though I did not oder anything. I want my money back!
Very likely it was the auto-renewal that took place.
In that case you agreed with it and the charge was fully legal.
For further info (and other things) see > https://www.avast.com/faq.php?article=AVKB24
Please (re)search before posting as things like this has been explained many times already.
The simple answer:
https://www.avast.com/faq.php?article=AVKB24#idt_0430