Los Osos Shell

Review: I bought gas at the Shell Station using my debit card and my Ralph's reward card expecting a $0.20/gal discount. After pumping gas I noticed that my receipt did not show the discount. I went into the man at the register and asked about it and he said my Ralph's reward card had no points on it. I saw his scan my reward card and told him that he was mistaken. He said there was nothing he could do. I went to Ralph's and they scanned my card and I had 225 points. Why would he say I had no points when I did. Does he make more money if I pay the full price? It's only a $2.12 issue but I got there to get the discount. The man at Ralph's says they have had numerous complaints about that Shell Station. What can I do?Desired Settlement: Would like my $2.12 back.