Card cancellation

On the 19th May 2023 I received a text message from FNB saying my card has been cancelled and I should destroy me card because it is no longer active. I immediately checked my card as I know it expires 2025, then I went to the closest branch in Potchefstroom and indeed my card has been cancelled and the assistance cannot tell why my card has been cancelled. Now I am forced to apply for a new card which I did not cancel myself of which I am being billed for but it is not me who cancelled the card. I want full explanation and reimbur*****t from FNB because I did not cancel my card instead it was FNB and without any consent from me as the cardholder. Going forward I am actually going to close this account with FNB and bank with another bank because now FNB is doing unauthorized decisions by the account holder.