Disgusting I'll mannered service. Shocking

Good day. My experience with this couple was to the extreme. They came from India and opened businesses in South Africa but the attitudes is disgusting. The lady by the name of Parul ordered with me a Indian snack called chevro. She instructed me to place it in packets so her husband can sell it in his restaurant/ takeaway. She will pay when I bring it. So the next day it was done as per her order. When I went to deliver it to her. She said I'm must drop it off by her husbands takeaway. She will call me. I did as I was told. When I went to her shop she was not there. But on my receipt I did write NOT PAID. Then she calls me and tells me that her husband is shouting at her and I must go fetch it. How can I leave food stuff in her takeaway and go back to back to fetch it after 2 days. So I told her I can't do that because it was with her for 2 days. It may not be a lot of money but it's a principal behind this matter and she was liable for payment. Her husband called me and swore me and was screaming at me. Since then they have never called me to pay. Contact details is ***