Fix Version autoupdate

[IPF Digital AS]

Hi, 

We're using Automation for Jira and recently we wanted to create Automation Rule that copies Fix Version value from Story to all Sub-tasks under this Story. The trigger here is each change of Fix Version field value. Attached is the screen with the rule. 

Audit log shows that conditions are met, automation finds correct issues but can't perform edit on Fix Version field on Sub-tasks and throws errors:

Unexpected error executing rule: Duplicate key com.atlassian.jira.rest.v2.issue.FieldMetaBean@586b2aa0

Unexpected error executing rule: Duplicate key com.atlassian.jira.rest.v2.issue.FieldMetaBean@3c7528d5

Add-on support provided with the article regarding this case: 
https://confluence.atlassian.com/jirakb/createissuemeta-returns-duplicate-key-error-872016885.html

But in our case it doesn't work. We have only 

Have any of you ever had similar problem and can help here? 

This is how the automation looks plus the Audit log entry

[IPF Digital AS]

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