• Whatsapp update -WhatsApp releases updates for its iOS and Android apps on a regular basis. It's possible that WhatsApp isn't transmitting messages because you have a defective build loaded on your smartphone.
• Scroll down to WhatsApp in the iPhone Settings app. Toggle the switch next to Mobile Data to enable it from the following menu.
• If you choose this option, you will be able to send and receive WhatsApp messages even if you are not using the app. Open Settings on your iPhone and select WhatsApp. Then, to allow WhatsApp to use data in the background, enable Background App Refresh.
• Open the Settings app > Cellular > Cellular Data Options and select Low Data Mode from the following menu to disable the iPhone's low data mode.
• Clear the cache by going to Storage & Cache.

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