How to cancel a purchase within 14 days of purchase

Apple App Store terms (for Europe, at least) state an option to cancel the purchase within 14 days from purchase with no explanation necessary. Today, is my last day to do that.

Apple's reportaproblem.apple.com site states that "your purchase does not fulfil the refund terms". There is no email address given, or any other means to send Apple my indication of cancelling the purchase. Telephone support is closed for the evening, too. I've got no clue why my purchase is not within the terms, while it is made within the 14 days from purchase (June 9th).

Does anyone have any experience about such issues? And is there an email address that I can send my cancellation, so that I can prove to have made it within the 14 days, please?