błąd rzeczowy

This article is well written but has a factual error.

She wanted so much not to make any kind of factual errors.

If any factual errors remain, it is not for lack of effort to correct them on their part.

There must be something in family life that generates factual error.

There have been some factual errors that we ought to take note of.

I would, however, like factual errors corrected before press time.

There are, however, some factual errors in the point that you make.

Your article contains several factual errors I would like to address.

This article is full of factual errors, not sure how it slipped through.

The main thing is not to point out the 'factual error' because for the person talking it isn't a mistake.