I’m making a guitar and I extruted the outline. The face orientation is messed up. I have tried recalculating the outside and inside in normals also. The rectangle highlighted seems to be the only one with the correct orientation.
I have also tried adjusting the clip start and end, but this does not solve the problem.
Welcome 
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It also seems you have duplicate faces… in edit mode try Mesh → Merge → by Distance…
