Pick n Pay Store Account Promotion Headache

Pick n Pay Store account has been running their monthly promotion - ''Spend minimum R2000, receive R100 credit''. I did not receive the credit due to me for the month of February, and since the 15th of February have been trying unsuccessfully to contact someone from Pick n Pay/RCS for the issue to be resolved - they simply have been ignoring the emails I have been sending, even though I have sent the issue to 3 different email addresses. When I call the call centre I am also unsuccessful. I have also contacted RCS directly, and I have messaged Pick n Pay on Facebook. I am not sure what else to do to get their attention. This is purely false advertising and I will not stand for it, nor will I stand for disgusting customer service. I will keep relentlessly pestering Pick n Pay until this is resolved.