Completely bad service

I app**** for a cellphone contract received a sms the next day saying I was pre approved got a sms later saying they were deducting the payment in the next 3 days. If they told me they would be doing that I would have told them that there was no money in my account. Now they have put my account in the minus and then had the cheek to send me another sms saying I have been declined. I have tried sever different no to contact them but have been totally unsuccessful. This is not how you do business.