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To ensure it will work, make sure you have an active and stable internet connection when accessing the WhatsApp application. What connection are you using? Is it Wi-Fi or data connection?
To isolate the issue, try to disable the data connection and then try using the Wi-Fi connection. To disable it, go to Settings and then Mobile network/Cellular. Tap the data connection to Off and then check if you're able to use the application. Do it also the other way around to see if you can use the application when connected to data connection.
my people contacts appear in ALL whatsapp list but not able to chat. I have to save each no. seperately on my phone to start a chat............can anyone help