Airtel — very very slow internet speed

Address:

New Delhi, Delhi, 110059

My airtel number is [protected] but now i regret why i have port my previous connection to airtel. I am facing this slow internet speed in every location so far though internet setting is already on data roaming and LTE but i am not able to experience so called fastest airtel internet. Even i have complained on customer care number in this regard (Ref no. for my request is C4GSP[protected])
I dont want to stand on terrace in this winter to send a single message to someone because of this so called fastest airtel service.
I was suggested by someone to abuse those customer care people 2/3 times to get resolved, but i guess never the less my problem will be solved by this complain as soon as possible.
Else i have to port my sim again to any other company network.
Put my complaint on the top of your priority list or forward it to the concerned authority.