Your project is complete, but you realized something was missing.
Login in to your Penji Dashboard
Click on the word Complete
Then click "Reactivate Project"
Read the prompt asking you to confirm your action and replace the project that you need to be worked on immediately.
Although this happens often, we highly recommend using the "On-hold" feature instead. This way you will know that the project isn't actually complete, but instead needs a final revision/confirmation from your customer/internal team.