copy value from one issue type and show it to another issue type

[mohammad lavasani]

i want to copy value of one customfield_xxx in the issue type Plan and show the value in the issue type Task when create. by automation for jira 

[Bill Sheboy]

Hi @mohammad lavasani -- Welcome to the Atlassian Community!

Would you please clarify the problem you are trying to solve?  It seem that you want:

When an issue is created,
copy a custom field from another issue,
using an Automation for Jira rule.

If you have started a rule, please post images of the rule, an image of the audit log details, and explain what does not work as you expect.

If you have not started a rule yet, please try to create it as that will help you learn about rules.  To get you started on creating your rule, please refer to these documentation and example sources: 

• https://www.atlassian.com/software/jira/guides/automation/overview#what-is-automation
• https://www.atlassian.com/software/jira/automation-template-library#/rule-list?systemLabelId=all&page=1&pageSize=20&sortKey=name&sortOrder=ASC
• https://support.atlassian.com/cloud-automation/docs/jira-smart-values-issues/
• https://support.atlassian.com/jira-software-cloud/docs/use-advanced-search-with-jira-query-language-jql/

Kind regards,
Bill