If you wish to prevent other Path Talk users from being able to do this, turn off Searchable by Phone Number in your Settings.
- Go to your settings screen by tapping the Me icon on the right side of the menu bar
- Scroll down the settings screen to the Privacy section
- Toggle off Searchable by Phone Number
This will not remove you from the People Lists you have already been added to, but it will prevent you from being added to further People Lists by phone number.