"Has anyone ever dealt with this before?"

You can google it; every investment house seems to provide a flier for how to handle this. But the IRS is your best guidance.

The earnings are considered earned and received in the year the excess contribution was made. You can leave it in and pay the excise tax, take it out, or apply it to the next tax year (absorb it as 2021). If you take it out by the timely filing of the tax return, it's as if it never happened. If you timely filed your 2020 tax return without withdrawing a contribution that you made in 2020, you can still have the contribution returned to you within 6 months of the due date of your 2020 tax return, excluding extensions. If you do, file an amended return with “Filed pursuant to section 301.9100-2” written at the top. Report any related earnings on the amended return and include an explanation of the withdrawal. Make any other necessary changes on the amended return. Applying excess contributions. If contributions to your Roth IRA for a year were more than the limit, you can apply the excess contribution in 1 year to a later year if the contributions for that later year are less than the maximum allowed for that year.

What you want to read is Pub 590 and 590-a.

The 1099-R that is issued should have a code P in it, for Previous Year.

https://www.irs.gov/pub/irs-pdf/i1099r.pdf