Yes. The code G Form 1099-R must be corrected to exclude the amount that was an excess contribution so that it shows only the amount that was actually eligible for rollover. Your 2019 tax return generally should be amended to reflect this corrected Form 1099-R. However, it won't change anything but the amount on line 4c of Form 1040, so might be sufficient to not amend and just respond with your explanation if the IRS questions this.
