False accusation of non payment

We visited Medicross Silverton on 2022/03/07 and paid with a Credit Card. The card machine's battery died during the transaction, so even though the amount went off my card, it wasn't linked to our Medicross account. On 2022/07/25 they started sending me statements claiming non-payment. I regularly responded with proof of payment based on my credit card statement. All my emails were ignored, so I visited the practice and spent some time with the person doing the accounts. She said that the relevant statements are old and she would therefore have to go through them another day, that she will take note of the case and be in contact if she needs anything and that I may ignore future emails from Medicross related to the account. Today (2022/08/31) I received a call from credit collectors telling me that I have been handed over to them for non-payment. Please get someone competent to contact me as soon as possible so that this nonsense can be sorted out.