debt order dispute

My premium date has been charged from the 20th of every month to the 17th or 18th by who no one knows, its been three month having unpaid debt orders , every time they say its fixed but nothing is done, who charged the date from the start and why don't they fix it, I have asked for policy documents its a year still waiting, just makes you wonder when I need to claim will they help me , I am upset my bank account has unpaid debt order charges , i want it fixed and pay my charges.