I want to split a polygon layer manually using the Split tool in QGIS however I'm getting an error
no feature slit done: The geometry is invalid. Please repair before trying to split.
I have checked the geometry using Vector-Geometry Tools-Check Geometry Validity and it reports 0 errors encountered.
I have tried creating a new simple multi-polygon layer and split works as suggested.
I can split the other polygons in this same layer, just not the one I'm interested in.
Any ideas for what else I can try?