Loan detetector equals loan shark

In June 2014 I tried to apply for a loan online. I made use of LDSA but was unsuccessful. I was also surprised when the R399 was deducted from my bank account. On 27 Nov 2015, 17 months later, I received a threatening sms that the amount is still outstanding. As I am in a position to pay I paid the amount to avoid being black listed by them. Now I keep on getting emails from their lawyers that I still owe the money. I mailed proof of payment as well as FNB to no avail. How do I get rid of them?FNB :-) R399.00 paid from cheq a/c..356005 @ Online Banking. Ref.Ldsa. 27Nov 10:48