Airtel 4G dongle not detecting in 14.04 after upgrade?

I recently upgraded from 13.10 to 14.04 LTS. I have an Airtel 4G dongle that was working perfectly with 13.10 but after I upgraded, its not detecting it. But if I am starting ubuntu with dongle preconnected, then its again working fine. I am not getting this problem. Do you guys have some solution to fix it as I have to restart my lappy every time I am disconnected.

Thanks