Part of a quad becomes see through when viewed at certain angles

I notice it when viewing from a specific angle but if I move a little or change the direction the camera is pointing then it’ll go back to normal. I’m not really sure even where to start with this one.
I only render faces exposed to air and I dont have culling enabled in opengl. If you look closely you’ll notice that its not even a full triangle that isn’t being drawn because the top is still visible.
Anyone have any thoughts on what could cause this?

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Check to make sure that all 4 vertices making up the quad are co-planar.

Yes they are coplanar. It looks like it is being clipped but I don’t understand why like that and why not also clip what is closer.