Jewel-Osco review: Customer complaint

I shopped earlier today 3-5-2016, at the Jewels food at 87 W. 87th in Chicago. As I completed my check-out, I remembered the free product I was to receive on the mymixx item. The item was a 4pk of Annie's organic yogurt. The cashier Peggie was very nice and told me to get the yogurt and take it to customer service with my receipt and it would be cared for. On checking, I found there was no Annie's yogurt and went back to customer service. I stated my dilemma and spoke with a Felicia Smith. She advised me that there was no way she could verify that this was an item free on mymixx. She told me I should have copied the screen? to verify this product was free. She told me that anyone can come in with a piece of paper claiming they was to receive an item. I explained that I had written it on a note so I could remember the correct item. She was speaking in such a way that other customers could hear and I have never felt so belittled and degraded in all my life. As a Senior (71 yrs old), I would find it hard to start trying to work a con on anyone. I am a Christian and would do nothing to hurt or hinder at this juncture in life. Please find a way to help this young lady to be more sensitive in her interaction with customers