Here is your Help article:

https://proconnect.intuit.com/support/en-us/help-article/form-1099/common-questions-form-8889-proser...

Is the Help article generated right from the form within the program itself?

Which worksheet? You asked about something on a W2.

Per that article, you need to confirm that the amount from the W2 entry flows to Form 8889, that the right plan type was selected, and "Don't duplicate amounts already shown on the W-2." If you enter the amount twice, you likely have an overcontribution which will be seen as taxable income.

In the case of employer/employee HSA, all funds are considered to be from the employee, even if they are employer contribution. That's why you do not enter the amount separately, again, once you entered everything with the boxes and codes from the W2.

Other errors include contributing to an HSA when you are not qualified to do so, of course.