Rain check

Got a rain check for butter on March 15 at the11500Tecumseh Rd Windsor
Return to store 3. times to get some and always out or not in yet. ,My rain ck expires in 30 days which is April 15/20
Stopped in today to get my butter and they would not honor my rain ck.. Supervisor told me orders from Head Office as of today April 14/20.
Vey disappointed since I had made 3 trips in there already. If there not issuing rain ck they should at least honor the ones from a month ago. Very disappointed and unhappy with Shoppers.