Under Administration>Issues select "Issue Type Screen Schemes" and find the scheme associated with the project you are working in then click on configure. Does the Issue type Story have the same Screen Scheme as Epic? If so, then you should be able to just edit the issue type field in the issue (assuming you have permission). If the schemes are different then you can try using move.
In the issue there should be a "More" button. Click on the button and below "Convert to Sub-task" should be an option to "Move". You should be able to move the issue to story and choose what to do with fields that are present/required in one scheme and not the other.
Hi, Jira users! Do you use Jira alongside Microsoft Teams? We want to hear how you’ve used the power of Jira Cloud and Microsoft Teams (via the Jira Cloud for Microsoft Teams app) to achieve a team...
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