When a notification shows as "Delivered" on our system, it means we have successfully sent the notification to Google or Apple's servers which distribute the notifications to subscribers.
The following are reasons why notifications may show as "Delivered" on the NotifyVisitors dashboard or API, but are not visible on your devices :
1) Network issues
The network / WiFi you're connected to, may have closed your connection to Apple or Google servers'. Try disabling and re-enabling your internet connection. See our Notifications delayed topic for more details.
2) Background Restricted Apps (Android P or newer)
Starting Jan 2019, FCM will not deliver messages to apps which were put into background restriction by the user. Once your app is removed from background restriction, new messages to the app will be delivered like before.
3) App has Push Permissions Disabled
Check the notification setting under Settings → Apps.
4) Low Power, Energy Saving, Do Not Disturb Mode
Some devices have a specific battery optimization that will stop notifications from showing.
Settings → Battery → Battery Optimization or Adaptive Battery → Find your app and press Don't Optimize.
5) App is Force Stopped
When an app is in a "Force Stopped" state most events including GCM/FCM messages for push notifications will not be received. An app can be placed in this state in the following ways:
a) Go to Settings → click on Apps, then press "Force Stop".
b) Long press the back button on some devices.
c) Using a 3rd party task killer, like Greenify.
d) Swiping away your app while remote debugging it.
- Not the same as viewing the logcat but launching your app as a remote debug process.
e) Swiping away your app from the recent apps on list on a Xiaomi device.
f) Automatically on some devices due to custom Android tweaks done by manufactures. Steps below on disabling this.
Check your app in the Auto-start Manager.
Step 1: Settings → Advanced Settings or Power Saving → Battery Manager or Protected Apps → select the app to protect it.
Step 1: Settings → Permissions → Manage Auto Launch → select the app to protect it.
Settings → Power Manager → Background App Management, select the app and ignore it.
Settings → Apps or Advanced or Battery → gear icon or Recent Apps Management or Apps not optimized or Battery Optimizations → App Autolaunch or Ensure Normal clear enabled or Don't Optimize or Advanced and toggle your app.
Disable battery usage optimizations
Tap on the battery icon. Go to Power Management → STAMINA mode → Apps active in standby → Add your app.
Security (App) → Permissions → Autostart - Enable your app__Settings → Developer Options. Disable "memory optimization". To enable Developer Options go to Settings → About. Tap on MIUI 8 times. Full Instructions
- Normally push notifications do arrive quite quickly. The most common reason for notifications being delayed is the device had no internet connection or a poor connection and the notification does not arrive until the connection is made.
However, there are some other cases where we've seen them get delayed:
Some home and commercial WiFi routers will cause the device's connection to Google's FCM/GCM servers to be closed. The device later re-opens the connection and receives the delayed notifications. (Discussed here: https://groups.google.com/forum/#!topic/android-gcm/Y33c9ib54jY)
Some custom versions of the Android OS have a "power-saving" setting that can cause notifications to be delayed or ignored. For instance, Sony Xperia devices have a "Stamina Mode". (Discussed here: https://talk.sonymobile.com/t5/Xperia-Z3-Compact/Notifications-not-Working-When-Phone-in-Sleep-Mode/td-p/879641)
Some Android devices can enter a low power mode,when their battery is low that may cause slight delays in receiving notifications. It is more common on Android 9 devices with the New Power Management Restrictions.
- Image URLs need a direct link to the image, no redirects allowed. In most cases, a direct link will have a file extension like .png or .jpg.
This will not work: https://pixabay.com/en/architecture-travel-sky-building-3095716/
But if you right click the image and open in a new tab, this will work: https://cdn.pixabay.com/photo/2018/01/21/01/46/architecture-3095716_960_720.jpg
The server hosting the image may have went down or could not handle the amount of downloads.
Every single device that receives the notification needs to download it. If the servers cannot handle the traffic, the image will not show.
It is best to host resources on other servers if possible.
Make sure the rich image you are sending contains the actual file extension and is a direct link to the image with a full URL. Redirects and URLs without the proper http or https protocol and image extension will not work.
If the image does not exist, the push will be sent without the image. The image is resolved on the app, so the push will still be sent, but the image URL will not return an image, and it will be shown as Standard.
If the network is not available or poor connectivity or any fluctuation occurs, then there may be a chance of image not being downloaded and it will be shown as standard.
If the image size is larger, and network is poor, then the image will not be downloaded and it will be shown as standard.
There may be a chance(s) of image getting corrupted while loading, then also it will be shown as standard.
Updated over 1 year ago