Merlin Leroy doesn't want to refund my money, they keep lying to me

I paid for gas bottle refill online at Leroy merlin store on the 28th July, on the 31 they sent me a message that they have canceled my order I immediately called them to ask why my order was canceled the agent said she's not sure she'll check and get back to me, she never did I then called the gas company to ask why order was canceled they told me I'm staying outside the delivery area. On the 2nd I called Leroy Merlin to ask them why haven't I recieved my refund, was told they canceled order but didn't processed my refund and they told me they'll contact Finance to refund me, till to-date I have not received my refund for service I didn't receive. They keep telling me they'll speak to Finance. Merlin Leroy doesn't want to refund my money and I need it so that I can pay gas refund in a company that will be able to deliver, I cook with gas stove now I'm forced to use electricity stove because they don't want to pay back my money