Can't create/save a task or sub-task for an Epic, New Feature or Task

[Melissa Nielsen]

When I create an Epic (and save it) then create a Task under an epic, I am getting the following error.  

"We couldn't create your child issue.  Check your connection and then give it another try." 

I don't have a connection issue because I am successfully making and saving all other edits.  I get the same response when i try to create a sub-task under a Task or New Feauture. 

Any guidance on how to fix the issue would be great! 

[Petter Gonçalves]

Hello @Melissa Nielsen

Welcome to Atlassian Community! Sorry to see you are not being able to create sub-tasks or Stories under your issues/Epics. 

Please, try the step below so we can better troubleshoot the problem:

1 - Is the problem happening only for a specific issue in your site or is it happening for any issue?

2 - Can you try to reproduce the problem in a different browser? Additionally, provide us with errors returned in the Javascript console of the browser.

3 - If a project has a default assignee but the default assignee does not have the assignable user permission, users will be prompted with the generic error you are seeing when creating a subtask through the new issue view:

Generic error message in the new view when creating a subtask

That being said, can you check if the default assignee under project settings > Details have the "assignable user permission"?

4 - Check if you don't have required fields to fill in the issues you are trying to created, as mentioned in the bug below:

Cannot create subtasks if there is a required field on the new JIRA issue view. 

Let me know if this information helps.