If you are still logged in on your profile:

Go to your patient profile on the website and unlink the login phone number.
You will be logged out and you will be asked to link a new phone number to your account next time you login. Keep in mind that until you do so, anyone who has your box code can log into your account!

This is only possible on the website, not in the app.

 

If you are already logged out:

Contact your care team or physician, they can change this is in your patient profile.