CorelDraw X7

I created an object using the bezier tool (to create 2 sides of a triangle) and then I used the 2 point line to create a slight "S curve" to close the shape.  I used "combine" to close the shape and then I "Powerclipped" a picture of grass inside of it.  It looks good, except I have a thin green line underneath the right side of the "S curve".  Does anyone know why that happened and how do I eliminate it?  Thanks for your help.