user did not back date customer account creation date/site date, how to back date?

Summary:

Our users accidentally created a customer without back dating to prior year, and we've tried to upload a correction multiple times but the site dates wont move back.

Content (please ensure you mask any confidential information):

How do we move the dates back? They need to be moved back to 2023. We were able to back date the account creation date, but not the site info. We keep getting the error: The source reference SITE_ORIG_SYSTEM_REFERENCE of the parent entity HZ_PARTY_SITES is either invalid or belongs to a different entity. Enter correct value for parent entity. but we can't seem to find how those are supposed to map together on the upload template.