Unroutable section

There is a section local to me marked in the map as a path, but which is in fact an unclassified byway that is navigable by bicycle, but th emapping refused to allow me to select that section as a route.  At the same time it quite happily routes through nearby fenced off and secured Ministry of Defence establishment roads. 

Is it possible to submit correction information to OpenCycleMap/OpenStreetMap?  

The areas concerned is in Corsham, Wiltshire, UK.  I have marked the prohibited routes in red and the byway that cannot be routed but should be in green in the image below: