I m using A 51 for three months, there is a real issue with net connection. Suppose I m using airtel for internet and I receive call on Idea network, internet is diconnected and it take almost 10 second to reconnect. As soon as i receive call VoLTE symbol disappears. This problem does not happen in my xiomi note 6 pro mobile.
Have you enabled smart dual sim in settings. If you enable that you can receive calls on other sim if you are on call in first sim. Similarly it works with data also.
Airtel Sim has some compatibility issues with Samsung Galaxy devices. hence for better results, I would suggest u to port to Jio. I was also facing huge problems when I was on Airtel.
To resolve this issue kindly follow the given below steps:
1) Check network operators and select automatically (Settings> Connections> Mobile Network>Network operator> select automatically > Tap on OK > Registered on network).
2) Check device in Safe Mode: Press and hold the Power key, when Power off icon appears > Press and hold the power off icon. To exit safe mode: Restart your device. Note: Your phone will restart after the update is installed. 3) Reset the device and before resetting the device make sure to create data backup of your device via SMART switch mobile application or http://www.samsung.com/in/support/smartswitch pc suite. Settings> General Management> Reset.
If the issue still persist, kindly register your concern in Samsung Members app (Samsung Members app > Get help > Feedback > Error report/ask question). Note: Please send device log files within 15 minutes of issue occurrence along with the exact issue details.
