Pay back the deposit

Good day

I booked a car (VW TSI POLO).On the 28th December at OR TAMBO AIRPORT and I asked the guy who assisted me if i can returned it at the nearest Branch which is Centurion opposite Centurion Gautrain Station on the 31st December around 15h30 and i was told that it will cost R150 Off which i didnt have stress about that , Now since then no deposit payment nothing (Dololo..Zero) i have been calling and I spoke with Khaya Duma and advise him that i sent a mail regarding this matter and he forwarded it holding deposit to release my deposit , Last nite on Facebook , I wrote to them asking what is the delay , a Lady by the name of Donna responded asking the ref number which is # ***7 and the Name Linda Xaba still not response the whole day today , I cannot be treated like this , what kind of customer Service are they giving no acknowledgement and response , no Apologies just quite .and as a first time Client I am so dissapointed