Loantracer

I have been trying to cancel my contract with Loantracer without success. I noticed the amount of R399 going off my account and realized that I have never actually made use of their service, and have moved all communication from them to my spam box. I cancelled the debit order, and after receiving an invoice from them paid my last months amount with a reference number supp**** by them, I also sent an e-mail on the 3rd of April expressing my wish to cancel the contract. Loantracer however ignores my request to cancel my contract and is continually sending me e-mails and invoices for payments already made. I do not know how to stop them.