SIGNED UP CANCELLED NEXT DAY AND THEY STILL DEBIT

I DECIDED IN MARCH TO TAKE OUT A SUBSCRIPTION THE 26TH MARCH 2015 WITH THE FOLLOWING DAY I DECIDED AGAINST MY DECISION AND CANCELLED I WAS ASKED TO SEND A CANCELLEATION IN WRITING ON THE 27TH MARCH 2015 AND I RECEIVED A RESPONSE THAT APPLICATION WAS CANCELLED. I HAVE KEPT PROOF OF ALL OF MAILS AND STILL ON THE 1ST OF JUNE THE DEBIT MY ACCOUNT...