Only admin users can log into SSO portal

What type of hardware are you using: Old laptop or computer
What YunoHost version are you running: 12.0.14
How are you able to access your server: The webadmin
Are you in a special context or did you perform specific tweaking on your YunoHost instance ?: nop

Describe your issue

Just found this weird bug on my work instance : standard users cannot login through the SSO portal, only admins can. When deleting and recreating a standard user, SSO login is possible, but i cannot do that for all users. groups username shows nothing weird so it must be somewhere in the LDAP config ?
Where can i find relevant info regarding this and what could i do to allow users to normally login ?

Share relevant logs or error messages

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