pbiviz start ERROR

Hi,

when i run pbiviz start i now get the following error -  

 error  LESS  style/visual.less :  The "data" argument must be of type string or an instance of Buffer, TypedArray, or DataView. Received undefined

to check that it is a common error i created a new visual that i did not edit and i still got this error. 

has anyone come across it and know how to resolve the issue ?

Tom