Have you looked at the MongoDB log file to see what’s being written to it? That should have the error that’s happening. If you can post the log showing the most recent attempt to start the process we can use that to help you out.
Also note that you shouldn’t ever run the MongoDB process as the root user (running with sudo) as this sets permission on files/directories that cause issues when you try to run as your normal user. Running as root can also lead to escalation of privileges and allow for bad things to happen.