The list as below may let you down but...Disconnection problem could be a compatible issue. Is your modem in that list for India?...

http://www.tp-link.com/en/support/3g-comp-list/?model=TL-MR3220&location=1144 From the above list, your dongle and region are not included. The problem you mentioned seems like a compatible issue....

It is a really annoying problem indeed. Sometimes, a chipmaker's driver can be helpful. Your guys may give a try.

You may try a different computer to install this card and see how it going...

Does wa830 work properly on your 3rd floor? Normally, to ensure a stable connection, you'd better not put a client device after a range extender.

;)Hope your problem will be solved after upgrading. Cross my fingers...^_^