Asda Refused My Refund Request For Frozen Items Saying Too Much Time Had Passed

For years I used Asda's Click & Collect service without any problems, however lately I have been irritated. When I went to get my weekly groceries about a month ago, several of the fresh goods I bought were really frozen. Thinking I would get a return as I had the previous, I declined to accept them. But upon looking over my bank records weeks later, I discovered no reimbursement had been sent. When I got in customer service, they promised to investigate it. I received an email yesterday stating that too much time had gone by so my refund request was declined. I start to feel let down. Asda wouldn't hesitate to intervene if I took groceries without paying.