Sometimes jobs accidentally get completed and you need to mark them as incomplete so that they will appear in your queue again. Here's the instructions on how to get a completed job to revert to incomplete.
Mark a job as Incomplete
1. From the jobs tab, click the status filter
2. Select Completed from the dropdown
3. Locate the job that you need to mark as incomplete and click on the job name
4. Click on Uncomplete
5. This will uncheck all tasks and put the job back into "In progress" status on the jobs list