The  1099NEC worksheet wasn't prompting (giving a pink error) for a place to include the income (where to link it to), so people were forgetting to actually get it included where it goes.....could that have been the issue, you entered the amount on the 1099NEC worksheet, but never told it where to include the money?

I rarely use the 1099NEC worksheet, I just include total business income on the Sch C, so it hadnt been an issue for me.

FWIW the last thing I do on a return before giving clients a final amount, is review  the Two Year Comparison worksheet for both the Sch C/E as well as the entire return.....and make sure it makes sense and nothing is missing in the current year that was there in the prior.