PRE APPROVEL DEBIT ORDER??

I placed an order online and did an application with one of the agents. I received a sms stating that I have been pre-approved and the money will be deducted from my account within the next 3 days. I can not understand why they deduct the money but I have not even been fully approved neither do I have the physical phone with me. They did not say this will be the case during the application process. What happens with the money when they later decline the request? I do not understand. If I had known this was going to be the case I would have thought twice before applying.