laser cutting advice and help

[the walrus]

Hi All.
Assistance needed from you laser cutting and cad experts.
I submitted some DXF laser cutting files to a well known company, the files where taken directly from the cad drawn plan and no kerf correction applied.
And the returned cuts do not match the plan.
Previous cuts performed by a now defunked co fitted a treat with three test models built with no issues.
Is this a machine set up problem or other?
Your advice wil be much appreciated.Thanks.
Cheers.
          John.