internet not working after installing usb dongle software

I am using Ubuntu 16.04. After installing the software for my Airtel 4G USB dongle, I am having a strange problem.

Internet through the dongle is working and WIFI while using the dongle on a router is also working.

Whenever I connect my Android device's internet via USB tethering or the Android hotspot, the internet does not work. I am sure it was working before installing the USB dongle software, but it will not connect now.

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