When importing comments to issues in team-managed projects an error is thrown

Issue Summary

When importing comments to issues in Next-Gen projects an error is thrown using the External System Import.

Steps to Reproduce

1. Create a CSV file containing Summary,Issue key,Issue id,Comment,Issue Type, Parent
2. Try to import the CSV file.

Expected Results

The fields are going to be updated and the comment will be imported.

Actual Results

The following error is thrown:

Workaround

What happens is that the importer will look for a Parent Association for the imported issue and if it does not exists it fails. To work around the behavior create a new Epic and add all the issues into it and then perform the import mapping the Parent -> Parent ID with an empty value.