Authentication Failed on captive portal with LDAP

Hello guys !
I have some issues about captive portal with LDAP authentication.
When I connect to the network on which the portal is configured, it is displayed correctly.
Then I try to connect and after a few seconds I get the message “LOGIN FAILED”
It seems that the traffic is not passing through the SpeedFusion during the attempt.
I’ve made several attempts during packet capture sessions, and in these captures there’s no trace of LDAP packets going to our Active Directory.

The account I created to read my AD is correct, as is the password.
It has the right rights

If anyone have some advices or solutions it’s good for me.
Thank you.

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