That’s the US code for number withhold, isn’t it?
That isn’t (necessarily) going to work outside the USA
#31# is the general code.
geckobeach.com/cellular/secrets/gsmcodes.php
3GPP : 22.030 Man-Machine Interface (MMI) of the User Equipment (UE)
portal.3gpp.org/desktopmodules/ … tionId=570