I have a csv containing 80k issues exported from Freshdesk that I want to import into JSM. I've attempted to do so using the External System CSV Importer, and mapped the "email" field from the csv to the "Reporter" field in Jira, but this results in every user being invited to sign up immediately, and worse they get a proper "User" created (with associated licence costs) rather than just a Customer access.
What's the proper way to import this kind of stuff?