********* Handover Account

I am very disgusted at the incompetence of the impact metering team. I recently moved from a property and followed their process of account closure. They deducted from my deposit to settle the bill which I was ok with however, handling of the outstanding balance was not done professionally. Firstly I received a call checking in when I would be making payments and I confirmed that I would do as such in a promise to pay arrangement. Paid half the amount then suddenly in barely a month of the account being outstanding they handed me over to debt collectors? Since when has that even been legal? What does the Consumer Protection Act say and what does Treating Customers fairly say? Suddenly the account is handed over yet they have been receiving payments often and I also have settled the account. Now I must go and pay the debt collector for the incorrect emails they sent over an error by Impact? This is totally ********* and unfair. No one contacted me to advise that they will be handing over the account nor was I in any contempt or resist to pay the account. There is no way it can be ethical that I am expected to pay their debt collector for interests that should not have been charged in the 1st place!