LDAP Authentication does not fallback to internal database

I have a sonarqube instance that was authenticating against internal users database only.
After adding an LDAP Connection to the internal Active Directory (according to : Delegating Authentication | SonarQube Docs) i have the following situation. Users not available in internal Database can connect successfully using LDAP. Existing users (same login id and same email) are only authenticated using the local authentication not via the ldap authentication.

When I read the documentation it states that the LDAP authentication has :

  • Ability to authenticate against both the external and the internal authentication systems. There is an automatic fallback on SonarQube internal system if the LDAP server is down.

Is there a way to have the fallback authentiction activated

Version SonarQube developer Edition

not existing users:

2021.07.26 11:37:29 DEBUG web[AXriI1ECtFoGL8CyAACN][jdk.event.security]  TLSHandshake: xxxxx.xxxx.com:636, TLSv1.2, TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384, 2046807913
2021.07.26 11:37:29 DEBUG web[AXriI1ECtFoGL8CyAACN][o.s.s.a.UserRegistrarImpl] List of groups returned by the identity provider '[yyyyyyyyyyyyyyyyyyyyyy]'
2021.07.26 11:37:29 DEBUG web[AXriI1ECtFoGL8CyAACN][o.s.s.a.UserRegistrarImpl] Adding group 'yyyyyyyyyyyyyyyyyyyyyy' to user 'zzzzzzz'
2021.07.26 11:37:29 DEBUG web[AXriI1ECtFoGL8CyAACN][o.s.s.u.NewUserNotifier] User created: feic01. Notifying NewUserHandler handlers...
2021.07.26 11:37:29 DEBUG web[AXriI1ECtFoGL8CyAACN][auth.event] login success [method|FORM][provider|REALM|LDAP][IP||][login|zzzzzzz]

existing users:

2021.07.26 11:42:15 DEBUG web[AXriI1ECtFoGL8CyAADT][auth.event] login failure [cause|wrong password][method|FORM][provider|LOCAL|local][IP||][login|zzzzz]