Airtel — signal problem since last 6 months

Address:

Adilabad, Andhra Pradesh, 504208

Iam using airtel prepaid sim from last 2 years. Am facing signal problem from last 6 months and i complained about it around 7 times, they just say your problem will be solved. Every time i call them they say same answer of it will be solved. And in last call ive asked about how many days will it take to clear, they were not saying and in last they said that am asking it again and again so they disconected my call.
*in first three calls they said to upgrade my sim to 4g - i did.
*in further calls they said to use a 4g handset for better network - i bought a new 4g mobile.
* and now in last two complaints from a month ago they just say it will take time.
And now they just disconnected call for asking commitment for how many days it will take for solving