I am in process of selling my house and just found out that Federal gov. has the Tax Lien against my property. It seems like a mistake due to the similar name. Someone has the same name as mine didn't paid the tax what they owed.
Who should I contact to get this corrected.

I would appreciate your response.

Thanks

Does this other person have the same social insurance number as you ?

If it is a Federal tax lien contact your local IRS office (or federal tax authority depending on your country). If it is a mistake then your different ID numbers should clear it up.

Does this other person have the same social insurance number as you ?

FYA, if it is in the U.S. we call it "Social Security number".