MERCEDES BENZ PLAYING GAMES WITH MY REFUND

I bought a car with Mercedes and I happened to be under debt review under Pioneer company. I sold the car and I managed to settle it up. A lady by the name of Keshrenne Nirmal from Mercedes Benz sent me an email on the 23 February 2021 saying I have a refund so I need to send the bank account from which the money was paid. In this instance it is Pioneer. The lady from Pioneer Samkelisiwe Buthelezi forwarded all the information. Mercedes Benz decided to do a manual payment which they provided a proof with no banking account into which the money was paid. \My question is, how can money be paid MANUALLY without a receiving account. I having contacting both parties, Mercedes Benz is insisting that the money was paid and it has not reached Pioneer's system today and there is no response.

I feel that it is unfair and I do not know why Mercedes Benz decided to let me aware of the money and now the money is untraceable from their side.

Any one with an advice, please.