2 Deposits still not paid out. Legal action needed.

It is now the 14th of december and we are still waiting for 2 of our deposits from thrifty car rental. One dating all the way back to the 14th of october and the other from the 22nd of november. Whenever I call either the phones are not picked up or they transfer me from branch to refund office and so forth. I'm convinced that they just do not want to pay. A story about a refund being authorized in october was given but no money has come in and fnb is not aware of any such transaction. If there is any legal action I can take please advice.