Payment made no stock for a month

We bought an aircon (online exclusive) on 12 dec 2018. After inquiring a couple of times as to when delivery will take place and no one getting back to us we received a call today stating supplier out of stock!! Still they advertise the same product online for R3000 more. Now after a month of waiting they tell me I have to wait 5 to 7 working days for a refund!!!!