Ok, this is the worst broadband connection I ever had. totally waste of money and 2500 device cost is too high to go in garbage.
it’s very simple, sim card network varies all the time, sometimes you get good speed and sometimes very bad. they put a device in your balcony so that signals can be enhanced but if there are no signals then what you can do.
So, my advise is don’t ever go with Airtel 4G broadband. the customer support is also worse I ever had. after complaining almost 15 times they don’t care at all.