Bad customer service

Royal tombstone Rustenburg refusing to fulfil thier promise on thier marketing plan saying the lady I was dealing with ****ed me and many other customers.I paid for my father's tombstone worth R17500 and I was told that paying it cash I will get a free double ply blanket however when I make follow ups regarding that they are telling me stories and refuse to share the head office contact details.I asked to be cc'd on the escalation email regarding the matter at hand howeve I haven't received any correspondence.They are now ignoring my messages on their WhatsApp number I am even worried that the might not even deliver the tombstone.