Complaint Review: SHELL GAS station at Randolph MA

Had 341 points on my Stop and Shop card. I did groceries today, and was out of gas, thus I stopped by to get filled up at Shell: open 24/7. They have the highest fuel prices in the street, but because I know I had 300+ points, I will be getting 30 cents off the gallon. Inserted stop and shop card, then my shell card, and placed fuel: no discount given! Nothing on the slip! Went to the attendant, whom I could not hear over the glass, and he just shook his head in his inability to help.

This system seems to not work, and save money by going to other gas stations, instead of depending on this silly stop and shop discount