In a project migration process how can I create connection between epic and story etc.?

[Mariam Hovhannisyan]

I want to migrate the Jira project from one instance to another. I can import all Epics, tasks, stories, sub-tasks with all components, assignees, labels, priority, statuses, etc. But I can not create a relation between epic and story, epic and task, task and sub-task, bug and sub-bug.
Thanks advance

[Trudy Claspill]

If you are using the CSV import to import the issues to the new instance, and you are importing into a Team Managed project, you cannot automatically link child issues to Epics. But you should be able to link sub-task issue types to their parent issues. Refer to this article under the heading "Creating sub-tasks".

https://support.atlassian.com/jira-cloud-administration/docs/import-data-from-a-csv-file/

If you are importing into a Company Managed project, you use that same method to link sub-task type issues to their parent issue, but for Epics you use a different field - use the Epic Link field in the child issue to identify the parent epic.