To disable the chat for all your trips:
- Go to Settings > Trips > Chat
- Uncheck the "Enable chat" option
- Save your changes
To disable the chat for a specific trip:
- Go to Trips and select the trip you want to disable the chat for
- Go to the "Share" step of that trip
- Inside the 'Trip settings' section, uncheck the 'Enable chat' option.
- Save your changes