How to split this mesh

Trying to split the attached mesh with a 45 degree line. I understand that you should project the curve on to the mesh and then use SPLIT MESH WITH CURVE – and this has worked in the past - but it does not seem to work now.

Any help would be appreciated.

Thank you.Split this mesh.3dm (268.7 KB)

Hi Cosmas - that worked here - but I’d move or extend the line so that it clearly goes past the mesh at each end - as is it is exactly on the edge of the mesh and tolerances may come into play.

;Split this mesh.3dm (363.1 KB)

Thank you, Pascal. It worked!