How to get this shape fixed?

Hi everyone, I wonder how to get an erroneous face fixed. The face is part of a shell where a fillet was generated. Use this DRAW script to reproduce:

restore shape.brep s
explode s E
blend r s 2 s_5
explode r F
checkshape r_1
vdisplay r_1
vsetdispmode 1

Does anyone has some ideas? Thank you! Best regards, Matthias!

Thomas Anderson's picture

I believe your input shape is a non-manifold shell and fillets probably don't support that condition.

Matthias K.'s picture

Thanks Thomas!
The shape could be non-manifold, I didn't check this explicitly. I attached a slightly different shape being identical in terms of topology and it's valid after the fillet generation. In fact, I did not encounter this problem before while processing hundreds of this shapes.

However, I wonder how the resulting shape or just the face r_1 can be fixed?