TRUWORTHS SENDING ME FROM PILLAR TO POST FOR PAID UP LETTER

I have paid Truwoths the balance of R400 on the 3rd of June. I've been sent from pilla to post. I just spoke to Consumer Friend and they confirmed that I owe Truworths more than R500 while I paid the balance in full at Loads of Living Fourways Mall. Basically, the company is refusing to give me a PAID-UP LETTER. My contact number is ********** - ID ********** 086. I wasted so much time on emails and airtime calling and writing to deferent departments.