My Ubislate 7C+ has a network related issue. I inserted BSNL SIM card in it. While browsing, the signal drops off. While searching network, tablet shows activity, but it does not work. When downloading, it gets disconnected.
The cause to this problem is the network reception. If the connection is not strong or stable, any attempt to download a large file will result in disconnection from the Internet service. The only way to fix it is to get better coverage for your device. If you have problems with the service, I recommend contacting Customer Support for the carrier network you have contract with or you're connected to.