Double Invoiced

I bought 3 vouchers online in October/November 2022. They appeared on my May statement again. Every time I query this, I get the message via e-mail that my query has been resolved and that my online profile has been blocked. This is the only response I keep getting. I still don't know why they are charging this to my account again or if they have credited it. I haven't received statements in years. I just check online everytime for the amount due. I feel that it is impossible to not have charged this to my account last year already and thus I feel it is completely unfair to expect me to pay it now.