Incorrect air-conditioning filter

On Saturday the 02nd of September, I was sold an incorrect car part by one of the gentleman working at MIDAS Randfontein. I was made aware by the mechanic and they were closed for me to return on the day.

I went back to return the part on Monday the 04th of September and I was requested to submit a purchase receipt. Unfortunately I lost the receipt and cannot produce it.

The mistake was from their side because one of the gentleman who first assisted me, went to my car to take the car details so that he can give me the correct service kit but the air-conditioning filter was wrong.

I cannot lose my money because I cannot produce a receipt when it was their fault. I didn't keep the receipt because I expected that the service kit was correct.