SAML setup not working?

[Stasky745]

Trying to setup LibreChat with Google SAML. My config has the following:

registration:
  socialLogins:
    - saml

with this envs (cert is correct):

SAML_CERT: /app/saml.pem
SAML_CALLBACK_URL: /oauth/saml/callback
SAML_ENTRY_POINT: https://accounts.google.com/o/saml2/idp?idpid=<idpid>
SAML_ISSUER: https://accounts.google.com/o/saml2?idpid=<idpid>
SAML_SESSION_SECRET: <string>

when starting the app, logs show the following:

app 2025-07-23 06:41:20 info: Configuring social logins...
app 2025-07-23 06:41:20 info: Configuring SAML Connect...
app 2025-07-23 06:41:20 info: [samlStrategy] Loading certificate from file: /app/saml.pem
app 2025-07-23 06:41:20 info: SAML Connect configured.

but when trying to go to https://<domain>/oauth/saml/callback I get a 404 page with details: "Error: No route matches URL \"/oauth/saml/callback\""

Trying to log in with SAML doesn't work either, it shows a 403 error with Error: app_not_configured_for_user, but the fact I get a 404 on the callback URL I imagine that might be the case.

I've seen this in the logs before too, though I couldn't reproduce it:

error: ErrorController => error SAML assertion audience mismatch. Expected: https://accounts.google.com/o/saml2?idpid=<idpid> Received: https://<domain>

Everything is correctly set on Google's side, and following the docs it's also correctly set on LibreChat. What am I missing?