Fortigate SSLVPN "some users are not using two factor authentication"

My FG has SSLVPN service configured that gives remote users access with username/password via LDAP with Mobile FortiToken or OTP via email double authentication activated for all users.

Some users have reported to me that they can access by simply entering only username and password and is not asked to enter the token.

How can this happen if all users have enabled double authentication for access to SSLVPN?

Attached the error shown on FG (firmware version 7.0.17).

User configuration:

# show user local xyz
config user local
edit "xyz"
set type ldap
set two-factor fortitoken
set fortitoken "FTKMOB11016D9D2B"
set email-to "xyz@xyz.com"
set ldap-server "LDAP"
next
end