This article provides guidelines on verifying why a field is NOT being copied when cloned.
Instructions
If you find yourself in a situation where a certain particular field is not being copied, please check the followingask yourself two questions:
Is the field included in the exclude fields list?
If the answer to this is YES, remove the field from the exclude fields list.
A field on the exclude fields list will not be updated and will be empty/cleared on the cloned issue.Is the field in context and on the screen?
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If a field is not on the screen, that field value cannot be updated
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If the field is not appearing on the screen
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, you need to add it. Follow this article for that: https://support.atlassian.com/jira-cloud-administration/docs/add-a-custom-field-to-a-screen/