fradulent account from mass build

I am very upset with teh bad service I am geting fro mass build,I have never had any business or account with them.I went to my bank to ask for credit but it got declined because they say i owe mass build 21000.00 It is a fradulent account under my name but however each time im contacting them they won't help me they say they have no idea of what I',m talking about.This is affecting me my time and my family because I can't get credit because of them.Please someone help..my number is ********** 554