Bad service One 2 One

My father have a contract with one 2 one, For some very odd reason his number is Rica Barred, he have been i store many times to get helped they call the one customer service but they are just so so useless, they have been sending him from Pillar to Post and still the phobe is Rica Barred, call centre agents that want to be the only one talking and not giving client a gap to say something. Cant they just release him from the stupid contract and put his number back on pre paid as this ONE 2 ONE is useless they cant help when a problem arise