---
agentTools:
  projectIndex: https://docs.nvecta.com/llms.txt
---

# Troubleshoot: “Mismatch SenderID” error

If your Android app fails to receive push notifications and you see Mismatch SenderID error while sending the notification, follow this checklist in order.

## 1. Make sure `google-services.json` is in the **app** module

Place the file at:

`<project-root>/app/google-services.json` (not in the root project or another module).

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> Tip: If you use product flavors or multiple app modules, ensure each application module that builds an APK/AAB has its own correct google-services.json.

## 2. Verify the **Sender ID = Project number**

Open Firebase Console → **Project settings → General** and check **Project number**.

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It **must match** the `project_number` in your `google-services.json`.

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## 3. Confirm the same Firebase project is configured in **NotifyVisitors**

* In the **NotifyVisitors** panel go to **Settings → App Push → Android tab**.
* Check the **Sender ID** shown here.

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It must equal the **Project number** from Firebase and the `project_number` in `google-services.json`.

> If you manage multiple Firebase projects, make sure you didn’t mix files (e.g., dev vs prod).

## 4. Re-upload the correct auth file

If anything looks off, re-download from Firebase and re-upload to NotifyVisitors:

1. In Firebase Console, download the **service account** JSON/auth file required by NotifyVisitors (per their dashboard instructions).
2. Upload it again in the **NotifyVisitors** dashboard (**Settings → App Push → Android tab**).
3. Rebuild your app.

> This ensures your server credentials and your app’s Sender ID come from the same Firebase project.

## 5. Verify at runtime (SDK v5.5.4+; debug only)

Open **Android Logcat** and look for:

```
Firebase Project ID: <firebase_project_name>
```

* If this printed **project name** matches your app’s Firebase project, your generated token aligns with the correct project.
* If it differs, you’re building with the wrong `google-services.json` (or wrong build variant).

## 6. Full setup guide

Cross-check every step in the [NotifyVisitors doc](https://docs.notifyvisitors.com/docs/register-fcm-keys).

## Summary

* **Sender ID = Firebase Project number**
* It must match in **three places**: `google-services.json`, **Firebase**, and **NotifyVisitors** panel.
* Re-download/re-upload auth keys from the **same** Firebase project and confirm Logcat shows the correct project at runtime.