Cancellation Illustrator

Can somebody tell me how on earth I cancel my Creative Cloud single-app membership for Illustrator - Adobe Illustrator CC monthly (6 months with monthly payments). I never got to use it I wanted to make a tryal. It is not possible to cancel online, at least not on the Brazilian site. I'm told to contact customer service. There are two possibilities for contacting customer service: Telephone, but I'm not willing to pay for a call from Brazil to (I assume) the West coast of the US. Or Live Chat, which despite repeated attempts yesterday and today simply does not work - I get no response, the app just times out after a minute or so.

At the moment I see only one possiblity to stop Adobe taking money from me for the rest of my life. I'll have toblock my credit card and start some chargebacks. Ridiculous.