Capital One Debt Collection Complaint

Capital One Debt collection department,

Credit card Cont'd attempts collect debt not owed Debt is not mine Ohio

i have tried several times to talk to them. They have refused to supply me with the social security used.i have sent a dispute letter and they say they didnt get it but refuse to send me another one. All my credit cards and loans are paid on time and i am not late on one of them. Please help me this company is ruining my company.