Harassment at its best

I hv an account with Homechoice and Its more than two yrs now, I first bought bedding and and did a debit order arrangement and the whole amount was paid, then I decided to buy home appliances and made a debit order arrangement again, Homechoice decided to stop de biting frm my bank account and I started receiving irritating calls from their consultants, I ended up making an arrangement to pay more than I was expected to pay so that I can cover arrears that am in because of Homechoice. Now am being harassed called more than once a day by consultants to check when am I going to pay whereas I made a debit order arrangement, am even receiving threatening messages two days after they debit to say i failed to pay and am reported to the credit bureau.