• Turn your device off and on again to restart it.
• Open the Settings app on your device, go to Network & Internet, and toggle Airplane mode on and off.
• Open the Settings app on your device and go to Network & Internet > Internet. Tap the Settings icon next to your carrier. Turn on your mobile data.
• Open the Settings app on your device, then tap Apps> WhatsApp > Mobile data & Wi-Fi> enable Background data. Install the most recent version of WhatsApp from the Google Play Store. Upgrade your Android device's operating system to the most recent version available.
• Instead of a check mark, look for a clock indicator next to your messages. If this is the case, it indicates that your messages are not being delivered.
• Check your device's network signal to see if it's flickering or empty.
• Turn Wi-Fi off and on in your device's Settings > Network & internet > Internet.
• Connect to a variety of Wi-Fi hotspots.
• Ensure that Wi-Fi is turned on while in sleep mode.
• Restart your wireless router.

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