Unhappy customer

Hi Peter I'm so unhappy about my truworths account. So the thing is I paid my truworths account on the 25 of April EFT so I put my name as my reference instead I was supposed to put my account number as my reference so now they did not get that payment I go to my bank asking about the R500 I paid and they said that money is out of my account. So I also ask for the statement of that R500 so I let the lady at truworths help me send it as proof that I did pay my account. Now the call me all the time and said I'm in arrears with R779.93.To be honest I made payment every month. So i need to know where did that R500 go Anyway i did call them to tell them about my payment in april.