Refund not being given. Poor customer service in store

Purchased airconditioners. Store manager at hirschs milnerton refused to give the refund in store. Purchase was through a credit card and the store says that the limit on card refunds is R10,000. The refund required is R19,000. Also a call to directors did not rectify the problem. Additionally, very poor service from the store manager. Customer service training is required by the store manager.