Pathetic service from Brands online - refusing to refund money

I made a purchase for a pair of shoes on the 27th of April 20, The shoe was available online and payment was made. I then received an email on the 2nd of may informing me that the shoe was not available and that I could choose to have my money refunded. I requested a refund and to day I have not received my money nor a response. Pathetic would be an understatement. All I want is my money back.