An issue does not get synchronized and appears in the troubleshooting section with the category 'Missing issue' and a message like 'The Issue PA-123 is preventing the Issue PA-234 to be processed.'.
There are two possible causes:
- A subtask is being synchronized, but its parent task is not synchronized.
- An issue is assigned to an epic and the epic is not synchronized.
- Check why the required issue is not being synchronized
- It might not be in the set of synced issues - check your JQL filter and the Issue Type Mappings.
- It might appear in the troubleshooting with an error which prevents its creation.
As soon as the parent/epic issue is being synchronized, Backbone will try to apply the message again.