I have a model that I have printed parts from, then I made some modifications (not in the problem area) but now when I save the model, Sketchup 17 wants to repair errors and opens some faces that I cannot close after the Sketchup fixes are applied.I have tried closing the faces with lines, ThomThom Cleanup2, and Microsoft 3D builder on the stl. None have worked. I would like to fix it within Sketchup. I would appreciate some advice.

Please help

I didn't find the right solution from the internet.

https://sketchucation.com/forums/viewto … mp;t=67281
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