....because more than two sheet bodies cannot be joined together at a single edge junction.

I am modeling a large paint tray and created 1/2 of the model with surfaces. I then offset the surfaces to my desired part thickness & am trying to knit everything together & create a solid so that I can mirror this body & complete the model.

Every time I try to Knit the surfaces together and form a solid, I get a Rebuild Error: The pieces cannot be joined into manifold bodies because more than two sheet bodies cannot be joined together at a single edge junction.

I have been through the part multiple times from every direction to make sure I haven't missed trimming a surface, but am not sure what the problem is or how to fix it.

I would greatly appreciate anyone's help!

Thank you!