Connection consistency issue in E3276 dongle issue with Raspberry PI

Question

I am using E3276 with a Raspberry Pi that is running Rasbian OS. My application is to connect to internet automatically through sakis3g. I have written code to get a connection automatically whenever the connection is down, which is working fine now, but the problem is, it continuously works for few days (2 days) and then the dongle is not getting connection to internet at all (it says 'Failed to Connect').

The solution I tried which is working fine is, manually I remove the dongle from the Raspberry Pi and then connect it to a laptop running Windows and used to browse once in laptop and then connecting it to the Raspberry Pi. Then it works through my automated code, that involves sakis3g. This scenario works continuously, as I said, for few days and then it stops working.

I tried once a solution that passing AT+CFUN=1,1 (Modem Reset Command) at the instance of getting a Failed to Connect prompt. It was working. So I incorporated the same command in my code before getting a connection through sakis3g. It was also working. I was very hopeful that I had solved the issue, but again the problem reoccurred with the same scenario.