Nimble group refused to remove themselves from ITC irregardless of being paid up more than a year ago

I've payed off my debt with mixtelematics more than a year ago.Which listed me with nimble group.but tell me why does nimble group still list me on the ITC without removing me.ive begged them but they all seem not to care.its either they put me on hold or hang up on me.Nimble group js the worst.They ruined my life.financially and psychologically