Cant cancel order after website says I can do so????

I have ordered 2 pairs of boots yesterday (30/05/23) at around 08h20. Someone warned me about this website so i went onto the website again where it clearly states you can cancel your order within 12 hours. I canceled at 13h00 the same day on the email address supp**** on the website. When i received my confirmation of order email, I rep**** that they must cancel the order. Today i received an email from them stating i cannot cancel as it already entered the shipping phase which is absolute nonsense! I canceled roughly 5 hours after ordering! I blocked my card before the amount of R1200 went off. I am afraid to unblock my card now?