Yes. You can make the online request in this page.

All bookings that have been made directly with TAP (online, at TAP desks, at the contact center or in stores) can be changed if the tickets have been issued for more than 24 hours.

Bookings that involve ancillary services cannot be changed:
The following can also not be changed: bookings made through travel agencies, bookings made through the TAP Miles&Go (Miles) Programme, bookings made through the Corporate programme, bookings using promotional codes and group bookings.

If your luggage is missing, please follow these steps:

Create a TAP Account here. Once you have provided your details you receive an email with a link via which you can activate your registration and choose a password. This link is valid for 24 hours. After this period, you need to register again.