NCCI audit

Hello everyone. I am new to the forum and this is my first post. I had a question about NCCI classification codes. Has anyone run into having their W/C carrier reclassifing their outside sales people to anything other than outside sales code. I am currently going through an ordeal where my insurance carrier is try to change our code from outside sales to ROOFING class code. This would essentially put me out of business. Any experience with this and/or an NCCI dispute which we now have to go through?

Thanks TIG