Airtel — Regarding unnecessary usage of data

I am using airtel since 5 years and i was very satisfied with their services but i m very much annoyed with this network lately . From last 1 year its happening that all my data get exhausted on its own i dont use it at all . Firstly i thought theres a problem with my phone so i checked it everything was fine no updated were done nothing downloaded, i also keep my data saver on to save extra data maybe used by backgroung apps but then also i sleep in the night with 2 gb data for 24 hrs nd i wake up it says u have used 90% of your daily data . I m sick of this i have decided to quit airtel but i want to say this . You guys cost so much higher than every other service providers but you are dissapointing your customers . Every other airtel user is complaining about this issue . I have done my recharge 2 days ago and its all used up i have online classes to take now what i m supposed to do with no data since its all used up and I HAVE NOT USED IT I DONT KNOW WHERE ITS ALL GOING . Fix this if you can its very common issue with almost everyone who uses airtel network .