Airtel — huge delay in broadband service request and unjustified fine charges

Address:

Gautam Buddh Nagar, Uttar Pradesh, 201301

I had registered a service request with airtel for broadband plan migration from broadband rs.899 plan to rs 799 plan. The service was supposed to be completed by 16 nov, as per the text message:
"dear customer, our technical team is working on service request no.[protected] for your airtel fixedline/ broadband id[protected]_dsl. We will call you soon and you can expect your request to be resolved by 16 nov 2019 07:30:00 pm"

It has been over a month, but the service request has not been completed, even after multiple reminders over email.

Moreover, while i was waiting for the plan change to be carried out, airtel added a rs.100 late payment fee on this month's bill. See image attached.
The "late payment fee" is unjustified because i was told by customer care that after plan change i would get a consolidated bill, and i was waiting for that to happen.

I urge airtel to reverse the unjustified "late payment fee" and also complete the service request at the earliest.