Weird Surface showing after boolean - Rhino 7 for Mac

First image is before Boolean Union of a simple shape, Second image is after. This is like a phantom surface yet when I go to shaded it is still showing. I restarting thinking is was just a video issue but that wasn’t the problem.

Another pic from the other side, there is nothing to trim out…

I Think the problem is in areas like this:

where the trimmed circle touches the surface edge. if you can move or decrease the size of the hole just a bit, should be ok.

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Thanks for your response Diego.
The holes are actually intact and good. They were done well before the latest little Boolean operation.

Hello - without a file - in the state before the Boolean operation, it is hard to help. But, I suspect Diego is right on the money - a trim that hits an another edge like that is asking for problems.