Poor and Unprofessional service

I contacted Chubb the 18th March requesting a lesser fee as competitors were half the price, I did get and answer quickly and the person said he would come back to me, never did. Sent them mails telling them I was changing provider and that I was cancelling their service on 20th March as I got the same cover for 1/2 the price, also told them to come and get their radio transmitter which they have not done yet. A few weeks late I received a threatening phone call saying I owe a months contract, a contract by the way I do not believe I have as I have been a Chubb client for over 20 years and never renewed any contract, and that they would blacklist me etc etc. I went and cancelled my debit order at my bank but guess what, this does not stop Chubb draw from my account, all they need to do is change the amount and it will come off which they did, clever and if you ask me dishonest, fortunately I caught it in time and got my bank to reverse. I have now instructed them to cancel their debit order and to date no reply - no surprise there. All this for a client who has been with Chubb for over 20 years, pathetic.