In reading what @DianeC958 entered, she is not saying that you enter it as income. Since it was a Roth 401(k), you were already taxed, whether you over contributed or not.
What she does seem to be saying is that you need to tell the IRS that you had an excess contribution in the current tax year (2019 here). When I followed the steps in Turbo Tax and created my own 1099-R for the 2019 tax year, I did not incur any additional taxes owed. Note that I selected code 8 in box 7 that she corrects herself further down the post.
The major question I had is: for a Roth 401(k) excess contribution in 2019, do I tell the IRS in 2019 or in 2020 (when I get the physical 1099-R from Fidelity) about my excess contribution in tax year 2019. According to @DianeC958, the answer seems to be you tell the IRS in 2019.
