Trying to do the notification for all users.

android/app/src/main/AndroidManifest.xml

@@ -13,6 +13,7 @@
     <uses-permission android:name="android.permission.READ_MEDIA_VIDEO" />
     
     <!-- Permissions pour écrire dans le stockage -->
+    <uses-permission android:name="android.permission.POST_NOTIFICATIONS"/>
     <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
     <application
         android:label="Travel Mate"
@@ -62,6 +63,9 @@
         <meta-data
             android:name="com.google.android.geo.API_KEY"
             android:value="AIzaSyCAtz1_d5K0ANwxAA_T84iq7Ac_gsUs_oM"/>
+        <meta-data
+            android:name="com.google.firebase.messaging.default_notification_channel_id"
+            android:value="high_importance_channel" />
     </application>
     <!-- Required to query activities that can process text, see:
          https://developer.android.com/training/package-visibility and