Can the Post-function "Create issues and subtasks be used on Create? The reason I ask is I receive the error "We can't create this issue for you right now, it could be due to unsupported content you've entered into one or more of the issue fields. If this situation persists, contact your administrator as they'll be able to access more specific information in the log file. jira"
I've also attached the post function logic I have happening on Create.