An issue does not get synchronized and appears in the troubleshooting section with the category Can't perform transition and a message containing, e.g. Can't move (ISSUE-KEY). You might not have permission, or the issue is missing required information.
It is most likely that the configured workflow for an issue type has a condition on a transition which prevents the synchronization user from performing the transition.
In order to resolve this problem please either
- Check the status of the affected issue in the Jira where the transition should happen (error origin)
- Examine the workflow for this project/issue type combination and check the transitions from the status you identified before for conditions
- Extend or remove the condition so that the synchronization user is able to perform them
- Perform a retry for the affected issues.