Mesh is showing as grey

[JessWay1]

Hi everyone! I'm pretty new to using archicad (using the archicad 27 edu version) I'm trying to create a mesh with a grass override surface. I'm following a tutorial from my class and have done everything exactly right (I've gone crazy trying to follow it exactly) but my mesh is still showing as grey when I go into 3D. 

The automatic pen visibility is off, I've tried making a new mesh, outside of the site boundaries, on different layers - I think there's a setting I've accidentally turned on that I can't work out. Can anyone help!!

[Lingwisyer]

Check your Renovation Filter. Your mesh is set to Existing while your filter is set to Planned & Demolished? Renovation Filters have Graphical Override settings to allow them to highlight relevant parts of the model.

https://help.graphisoft.com/AC/27/INT/_AC27_Help/050_ViewsVB/050_ViewsVB-126.htm#XREF_69943_Renovati...

Ling.