Not attended fairly

Wednesday the 20th August 2020 around about 16h45 I was at Clicks Cradle stone mall to buy 3 Safeway Convection ovens on that special you buy 3 items and get 40% discount, unfortunately they were finished and i requested to check in other clicks Featherbrooke and i was told Featherbrooke closed at 17h00 of which its not true, also they checl Clearwater mall and there was nothing. I requested to buy a rain check since these items i am interested are not available then i was told they dont do rain checks on sale items. I raised this with one of the Managers of another clicks where i was raising my frustration and she told and confirm that its not the customers fault if the item is not available a rain check was the solution. I need intervention on this matter as i think i was treated unfairly