****ty service

nedbank debited twice for my loan instalment that time i am on track, ive never missed a month. i called the customer care, they told me that they have processed the refund but they refused to give me the call log reference saying that the system has not generate a ref for refund. its been 3 weeks since they said the refund is processed but nothing came to my ***+ taken and the consaltant said someone will call me but nothing. when i call, they hang up my calls. is this proper business practice to clients? this is a ****ty service i want my money back