[Flutter] Error 400: redirect_uri_mismatch - Google sign-in error

I have hosted appwrite project locally, enabled google auth and did all the oauth consent process as per the documentation. Now I want to run the Flutter project on a real mobile device. To forward the port, I used ngrok and got an IP. I have confirmed that it's working fine.

Made OAuth Client API for Web application on a project in GCP Console, got the Client ID, Client Secret and passed it for enabling Google auth for Appwrite project.
I have copied the redirect url from appwrite google auth console (which includes localhost/v1/....), and replaced the localhost part with ngrok url and put it as Google OAuth Client API redirect url.

Now, when I'm running the app with Flutter, it shows this 400: redirect_uri_mistmatch.

Can someone suggest any solution?

(P.S. The GCP project is in testing mode)

Ngrok might be causing problems...what's the URL of the page when you get to the Google login screen?

https://accounts.google.com/signin/oauth/error/v2?authError=ChVyZWRpcmVjdF91cmlfbWlzbWF0Y2gSsAEKWW91IGNhbid0IHNpZ24gaW4gdG8gdGhpcyBhcHAgYmVjYXVzZSBpdCBkb2Vzbid0IGNvbXBseSB3aXRoIEdvb2dsZSdzIE9BdXRoIDIuMCBwb2xpY3kuCgpJZiB5b3UncmUgdGhlIGFwcCBkZXZlbG9wZXIsIHJlZ2lzdGVyIHRoZSByZWRpcmVjdC...lzbWF0Y2g%3D&client_id=<MY_CLIENT_ID_FROM_GCP_PROJECT>.apps.googleusercontent.com

Oh...this is after getting to the error page. Is there another page before?

I'm trying to see the redirect URI that google receives

Are you asking for the redirect URI I'm registering in the google console? If so it is: https://<NGROK_IP>/v1/account/sessions/oauth2/callback/google/642359fa4410a79b34ee

No. I was asking for what actually gets sent to google

In your browser on a desktop, open the network logger and then browse to.

Then, you should see the redirect URI sent to google

I have a bit of dilemma here, does <Endpoint> refers to <NGROK_IP>?

https://<ngrok ip>/v1

<activity android:name="com.linusu.flutter_web_auth_2.CallbackActivity" android:exported="true"> <intent-filter android:label="flutter_web_auth_2"> <action android:name="android.intent.action.VIEW" /> <category android:name="android.intent.category.DEFAULT" /> <category android:name="android.intent.category.BROWSABLE" /> <data android:scheme="appwrite-callback-appid" />

you if added it in androidmanifest?