Debit order **** - Computech Credit Services / CreditPro (Pty) Ltd

I was online applying for a personal loan, it was my understanding I was applying with some banking institutions, then I receive an email saying my application has been sent to several banks, shortly thereafter, I received another mail stating my application has been denied. Then I have a debit order going off my account for R345 odd, during the application I had to fill in my banking details, so this is how they must have debited my account without authorisation. I then had the debit order reversed. Now I receive a Letter of Demand from a company called CreditPro, demanding services rendered, interest and expenses and fees from Computech Credit Services. When I google online, it seems this has happended to many people, seems both companies are very *****. What to do now?