Any time you want to manually submit a new travel confirmation all you need to do is forward it from your email in-box associated with your TripIt account to firstname.lastname@example.org. Once submitted you will receive a notification email from us once the new trip has been created or trip item has been added to an existing trip.
Remember, TripIt posts trip information by travel date. We automatically import travel plans into an existing itinerary if the dates overlap or are within a day of an existing trip. So, if you can't find your latest submission it may be in a previously created trip and not in a brand new trip.
Auto-Import: If you have a Gmail, Yahoo! Mail, or Outlook account you can set up automatic submission of your travel emails to TripIt by authorizing Auto-Import for your account.
Updated: Oct 30, 2018
Related Help Page: Problem with your TripIt submission