UVs for exported mesh

Hello,
The mesh output node shows clearly the “Export UV coordinates” as option, I select it but the mesh I get (when imported in ZBrush) doesn’t have UVs. Is there something not working or did I miss a step somewhere?
Thank you

World machine version?

I export all my terrains as meshes with UV coordinates. Haven’t faced a problem yet. I’m on wm pro 3011. I don’t have zbrush to test it though. Works in Blender, maya, and vue alright.