Hi there! I understand that your Trenitalia app isn’t recognizing or saving train tickets you bought through the website. Let’s get that sorted out together.

First, just to make sure, did you purchase the tickets as a registered user (logged in) or as a guest/unregistered user on the website? Sometimes tickets bought as guests require additional steps for the app to recognize them.

Here’s a step-by-step approach we can try:

1. Log In to the Trenitalia App: If you booked with a registered Trenitalia account, ensure you are logged into that same account on the app. Tickets are linked to your profile, so logging in helps the app pull your purchases automatically.

2. Add Ticket Manually: Sometimes, the app doesn't auto-sync purchases made on the website. Try manually adding your ticket using the code (PNR) and the email you used during purchase. You can do this from the app’s “Add Ticket” or “Manage Ticket” section.

3. Email Link Access: Check your email confirmation for your tickets. There may be a direct link to view or add your ticket in the app. Clicking that link on your Mac could help sync it.

4. App Update & Restart: Please ensure your Trenitalia app is updated to the latest version available for OS X 10.15 compatibility (if using the Mac app version or on a paired phone). Then close and reopen the app.

5. Reinstall the App: If the above steps don’t work, uninstalling and reinstalling the app can clear any cached data issues.

6. Validate Your Ticket: For some train types, especially regional trains, tickets need to be “validated” using the app by checking in before boarding. If this step is missing, the app might not display the ticket properly.

If after trying these steps your ticket still doesn’t appear or save, could you tell me if there’s an error message or code displayed? Also, did you try to add or view your ticket in the app on your Mac or on an iPhone/iPad?

This info will help me dig deeper for you. Looking forward to your update!