Airtel — Cheating by Forging in App

I use Airtel Dongle for Wifi. Every month I pay my dues on time. Airtel time to time stops working or slows down speed and now the Airtel app is not working... I have complained numerous times and sent emails. Just got some stupid calls but no resolution... this way my payment date has arrived but I cannot pay the bill. These cheats in Airtel will charge late fee and once I pay the higher amount they fix the app after so much of pain. This is a story of every a few months. Why cannot appropriate authorities take note of this and make sure Airtel is not able to cheat us poor customers who have no place to go for resolution???