Harassing me

MBD LC keeps on calling me and sending sms's for debt that is outstanding for Woolworths, Standard bank etc. They keep on asking for Tyrone Prince. I believe this might be working at our company and probably lifted my contact details from an email for his debts, but the more I tell them I am not the person, the more they harass me. I even furnished them with the telephone number of a person with the same name in our company, in case that is the person they are looking for. This is my company phone and they are really getting me down.