Horrible Accounts Management

I got an sms yesterday that tells me that I have been handed over due to non payment. Firstly I have a debit order running with you guys, clearly whoever is managing that is doing a **** job. Another thing as a customer, why was I not contacted to notify me of this debt issue? Because of your mismanagement of books this fell through the cracks I have to suffer? Do you guys understand the impact this will have on my name?

Now that I want to cancel my contract with you, you want to write off that debt. Suddenly I am important to you, I wasn't important enough when I remained your customer. You were not even courteous enough to contact me regarding your mishap. This kind of abuse is the reason why I need my contract canceled urgently and sort out that account.