Terrible service

Purchased a pair of tyres online on 28 September 2018, no communication as to when i can go to the store to fit them. I call back on 2 October 2018 querying the status, no one is aware of my order even though its been paid in full. A few hours later i am called and told that the tyres i want (yokohama) have been discontinued and am given options to fit other tyres which are of different brands, i dont want that and requested a refund. The store then tells me that they will submit this to head office and contact me. No one calls, but i get a credit memo, i dont know what this means but i assume that its proof of my refund. 3 days later and nothing. All i want is my money back but am being sent from pillar to post. I need to purchase another set of tyres but i first have to fight for my money, i dont get how that works.