This is usually caused by a problem with your internet connection or the settings on your phone.
Please try these steps to fix your connection:
- Reboot your phone (power off, power on).
- Update WhatsApp to the latest version. Go to Google Play on your Android.
- Turn Airplane mode on and off (Android Settings > Wireless & networks > More... > Airplane mode).
- Make sure that data is enabled (Android Settings > Data usage > Cellular data).
- Go to Android Settings > Data usage > Menu Button > make sure Restrict background data is unchecked.
- Turn Wi-Fi off and back on (Android Settings > Wi-Fi).
- Try connecting to different Wi-Fi hotspots.
- If you are often connected to Wi-Fi, check your Wi-Fi sleep policy (Android Settings > Wi-Fi > Menu Button > Advanced > Keep Wi-Fi on during sleep) and make sure it is set to "Always."
- Reboot your Wi-Fi Router.
- Contact your mobile provider and make sure your APN settings are configured correctly.
- Verify that you receive your Gmails on time.
- Delete and reinstall WhatsApp (Note: This will erase your chat history on your phone. Be sure to run a manual backup beforehand by going to WhatsApp > Menu Button > Settings > Chats > Chat backup > Back up).
- Upgrade your Android OS to the latest version available for your device.
If you are able to connect on Wi-Fi but not on your mobile connection (EDGE/2G/3G/4G), double check your APN configuration with your mobile provider. You must be able to send and receive non-web traffic in order to use WhatsApp.
Learn how to troubleshoot connection issues on: iPhone | Windows Phone | Nokia S40 | BlackBerry | Nokia S60 | BlackBerry 10
WhatsApp Support Team