Airtel - Excess Bill by Airtel

I travelled to USA on *rd Aug and in advance I asked to get international pack done,,after reaching US for more than **-** days I couldn’t use network as mostly it was no service and I had to go through airplane on off mode to look for network,,and even in network either call or internet used to work at one time,,I had submitted so many request for same but no resolution,,I went through so many troubles to get it solved due to time zone issues and ultimately I had to get one sim in USA to use as Airtel were super messed up,,now in bills I have been charged so much for so many things which I am not even aware of,,Kindly look into this and get back to me,,My half of the trip ruined due to network fuck up,,I am not going to request for anything as for the trouble and to ruin my half of the trip ideally as a courtesy airtel should cancel all extra charges which has been added to my account to my bill which is also less I seek,,My airtel bill is due as I have been asking for same and everytime I am getting a stupid message that request is closed but I don’t understand how it can be closed without giving me any resolution or call,,do a business but don’t make someone go through so much trouble for it,,Kindly cancel all charges and late payment fees so that I can proceed with bill payment,,Switching to postpaid is such a big blunder I did and now I regret it highly,,

I sent an email on **th and inform their Whatsapp service for the entire time for the same but no response or replies has been given by Airtel so far..Reliance has shown the true colors of these fraud telecom companies,, Once I get it sorted..I'll switch immediately