********** debit orders

I'm really upset, I signed up with chubb(national security & fire)at my old premises 3 years ago. We cancelled as we were moving, at the new premises they offered to to install at the new place I declined and cancelled. They cancelled it, now 2 years later at the end of November 2019 they just randomly decide to debit my account for a service I dont have. I reversed this, then called them spoke to Tumi in accounts who said there is no active account on my name. She gave me her regional managers email address Indreshni and Elsie, I emailed them telling them that they incorrectly debited my account. They haven't responded. Tumi said she will dispute it as well. No response!! It is now the beginning of January and they have debited my account again, now for an even higher amount. Their accounts department does not answer. I am now left to pay bounced debit order fees due to ******* debits that they do not want to resolve. If this is not resolved by the 15th of this month I have no choice but to proceed with legal action.