Prada Online Payment and Order Confirmation Problems

I made an online purchase from Prada's official website, but as soon as the payment was processed, my order was not confirmed and was subsequently canceled. Although the payment of 936 pounds was deducted from my bank account, the sale was not approved, leaving the funds in limbo. I received a refund of only 862 pounds back into my account.
When I attempted to place another order, I was again charged 931 pounds. If the discrepancy in the refund was due to the currency conversion from TL to pounds, I don't understand why I was charged 931 pounds for my second order. Additionally, I struggled for several days to connect with customer service regarding this issue.
I hope to receive clarification and a resolution to this matter soon. Thank you.