I am receiving call call for unknown person

Hi sir,<br> <br> I am karanam from sandton. I am getting everyday calls 5-10 times from African Bank and asking unknown person for me. I am telling every time this is wrong number and no such person, but they keep on calling at 10 pm night some time. When I ask why do you calling again and again for wrong number, they response like this, Some one given this as their contact number on our records, until we found that one we keep on call you this number, as we do not have any other contact. If some gave wrongly or wantedly wrong number how can they harass me day and night calling my number. I don't know how to action it. Kindly advice me.<br> I am getting calls from the below numbers. ***000. ***