Having an up-to-date, accurate telephone number on your account is essential to account security, and it enables you to receive validation codes and activate/deactivate up to two devices and web sessions on your account.
If the phone number is outdated or you don't recognize it, we recommend checking with friends and family members. You should also make sure that you are logged out of any public computers you may have used.
Then, please contact us at firstname.lastname@example.org to change the phone number. You should immediately verify the number, authorize your device or web session, and change the password on your account to one you've never used before.