My bank doesn’t have to deal with HMDA report (and yes I’m happy about that) but I did a quick search and found some useful information on the FFIEC’s website. Here is a copy of the section that I think speaks to your issue:
“What do I do if I find an error in my HMDA data file after it has been submitted?
Make the correction to your HMDA file and send in a complete resubmission; partial resubmissions should not be sent. See the data collection procedure change regarding data resubmissions. Refer to the next question, “How do I resubmit HMDA data?” for the resubmission guidelines.”
Here is the link to the website as well: https://www.ffiec.gov/hmda/faqtech.htm#srs6
I hope that helps!