Refunde and who to contact

Ive been charged for a premium avast, yet i have no recollection of ordering this nor any emails about it. Trying to speak with customer service is a nightmare. I can log in to my account via Avast on desktop however most of the links i go to to ask for a refund are completely blank web pages.
Ive used Avast free free many years.
there is no direct email to contact support as Ive been trying to find this out for weeks..
any advice ?