Trying to print a pattern to check bed leveling

Trying to print calibration pattern 300x200mm. .16mm high
Generate gcode button grayed out.
Also reduced the file to be 290x180mm
same result.
Does anyone know why? and how to do it?

What slicer?

The slicer is Luban.
Works well on Prusa Slicer

Can’t really help you there, maybe ask on Snapmaker Luban forums instead?

I think the software’s documentation or settings to see if there are any restrictions on the maximum print size or layer height that could be causing the issue. Update the software to the latest version to access any fixes or enhancements that may address compatibility issues. You can also use alternative software for slicing and generating G-code that might better support your specific print dimensions and settings.