Pioneer foods takes no responsibility for their products-Disgusting!

I purchased 4 bags of Spekko 10kg rice in October 2022. I then found in 3 bags that it became mouldy . I called in February to have a customer query lodged also sent through pictures via thier whatsapp number. I had to constantly call Pioneer foods to get feedback because they would call me just once and if they never got hold of me they would just send an sms and sit back till I followup again. I sent a detail email to them stating the problem and mentioning I threw away my purchase slip because i didn't see a reason to keep it. After speaking to about 3 different customer service agents on different dates each one failed to tell me that nothing can be done with out a receipt. I then called again on the did the agent then tell me that no refund can be done because no proof of purchase. I then asked to speak to a manager his name was Luciano. He advised that he will look into it .I got a call next day from him and he said that an apology letter will be sent. How is an apology letter going to solve my problem. R360.00 is a lot of money plus my calls . Its absolutely disgusting to know we as customers have no value with Pioneer foods and they take no responsibility for their products. It seems as if im lying