Web Portal
Make sure you are logged into the Web Portal
Navigate to the phone settings page, or find it manually by clicking on your name in the top left corner of the screen > Account Settings > Phone
Click 'Delete' above the phone number
Confirm by clicking 'Delete phone number' in the popup
Your phone number is now deleted!
Mobile App
Open the Safepoint app
Ensure that you are logged into an account
Tap the 'Account' button at the bottom right
Tap 'Profile'
Tap 'Contact'
Tap 'Delete'
Confirm by tapping 'Yes' in the popup
Your phone number is now deleted!