• If surfing works but WhatsAppdoesn't, contact your mobile carrier and system administrator, and double-check that your APN and router are set to allow non-web and socket connections. Alternately, you could try a different connection. Try mobile data if you're connected to Wi-Fi, or vice versa.
• Open the Settings app on your phone and go to Apps > WhatsApp > Data use.
• Make sure you don't have any restrictions on background data.
• For Google Services, repeat the procedures above.
• In your phone's Settings app > Sound > Do not disturb, make sure Do not disturb is turned off or that WhatsApp notifications are set to priority mode.
• Check your phone's Settings app > Apps > WhatsApp > Permissions to see if all of WhatsApp's permissions have been granted.
• or fix by trying this things:
• Turn your phone off and on or restart it.
• Go to your phone's Settings app > Apps > Menu icon > Reset app preferences to reset app preferences.
• By leaving your phone plugged into a power source, you can prevent battery saving mode from triggering.
• Go to WhatsApp > More options > WhatsApp Web > Log out of WhatsApp Web. Log out of all of your machines.
• Go to your phone's Settings app > Wi-Fi > Settings icon > Keep Wi-Fi on during sleep > Always to keep your Wi-Fi on while you're sleeping.

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