Bad customer service

I bought some items from Spree on the 20 June 2017, they sent me an email to say that some of the items are out of stock and they have refunded the money as store credit. They told me that if I want the money to be refunded to my credit card I should reply to the email which i did and they ignored it eventually I called them only then they refunded my money back to my credit card. On the email they said that they will compensate me with a R200 voucher for the bad service. To date I am still waiting for that voucher , I called them and they told me someone from marketing will call me. so far its been 2 weeks no one has called me.