We’re encountering an issue where a subset of users in the United Kingdom have their mobile phone numbers incorrectly flagged as invalid, despite the fact that UK mobile number signups are generally working and successful for the majority of users.
The user resets their password using the provided link.
The user logs in using their provisioned email address and new password.
The user is prompted to enter a mobile phone number.
The user selects United Kingdom (GB +44) as the country.
The user enters their mobile number, but the application reports it as invalid and suggests the number is incorrect.
Our support team has occasionally been able to work around the issue by instructing users to omit the trunk prefix (0) when entering their phone number.
Are there any recommended mitigation steps or configuration changes we can apply to prevent valid UK mobile numbers from being rejected in this scenario?
Have you added the phone number as a primary attribute to the user database that you are using or do you want to add it to their profile prior to them signing up?
Also, can you provide some examples of phone number which receive that error?
Usually, the prefix is not needed for phone numbers so it would make sense why trunkating it works as intended.
This error is occurring when the phone number is being validated client side during the Passwordless / SMS flow. Manually I could enter this number in the dashboard with no issue.
AS far as I have tested during the SMS flow on my end, the number gets accepted without any issues with or without the ‘0’ at the beginning of the number.
Knowing this, I am wondering if the sync between Auth0 and libphonenumber library could be what is causing this issue for some of your users.
I can see that your tenant is under a paid plan, I would highly recommend to open a support ticket on the matter so that one of our dedicated engineers can inspect your logs or tenant and have more information on the matter.
