unproffesional , disgusting , rude agents !!

I have taken a loan out at finchoice in the 2011 or 2012 i eventually requested a paid up letter in 2012 or 2013 and settled the amount as per settlement letter.debit stopped deducting from my bank.in 2015 i relieved acall everyday saying i owe 9000 rands, this amount is even more than the amount i had recieved from them.they keep saying they will look into the matter and get back to me.everyday a new agents calls to ask why i have made no payments and im having to explain myself again.agents are so rude they say ka okay someone will call you back and drop the call.why will you only call an owing customer 3years later? no post? no emails? no sms? Only a call 3 years later !! this is harrasment.annoyed by these fly by nights !!