Mobile phone number does match info from user directory 

The number registered in the organization LDAP/HTTP directory must be changed if a user changes their mobile phone number. A user can download and activate the app and generate one-time codes without being aware that authentication at the organization fails because the number has not been updated. The error message to the user can be "Authentication failed".

Check the user name and refer to the log for a description. The mobile phone number has not been updated in the organization user directory if the description shown in the figure is displayed.

Contact the person who has rights to change this in manages the organization user directory. 

Ask the user to try again after the directory has been updated