Worst customer care service

I placed a online order (invoice ***) that included 2xgirls parka jackets that was advertised for R299 each with a discount of R50 each. When I received the jackets and the invoice my discount was never added. I sent a mail on the 26th of May to *** with no reply. I phoned after not receiving a reply and was told my query would be escalated and they would get back to me. Still no response. I sent another mail the 27 May, 01 June and the 8th June just to be ignored. This is terrible cudtomer care and to top it off I returned a top purchased on my account at Mr Price Sport online, tried to exchange it on Sunday and they didnt have the correct size. I was told they couldnt credit it on my account and was given a voucher. When I tried to use my voucher yesterday there was R0.00 on. Shocking to say the least. As a regular customer I am very upset ubout the way you are handeling and treating your customers.