I have a Reliance netconnect+ zte Ac2737. It has an allocated data of 5gb per month. The modem works fine only after the allocated data is over, for which i have to pay extra to the provider. I tried contacting the provider, but it was not of much help. The system detects the modem every time. I assume that it must be a possible problem with the provider, so is there any chance it is the problem of Ubuntu 12.04 LTS 64 bit itself as i have no other reason to think otherwise an it works fine every time on windows.