Airtel - Wrong Amount Promised and Sold a Plan

I am a customer of Airtel, utilizing Broad band service and mobile phone network connections of Airtel. In April a lady called from Airtel and offered me a new plan called One Airtel/One Bundle plan where she informed that this plan will cost me a monthly Rs.****/- inclusive of all taxes, no other extra charges (which was confirmed twice with her) and it will accommodate an Airtel Broadband service+* mobile phone connections (which were prepaid initially but were converted to postpaid as per the requirement of plan). I had also confirmed during the call that what is the possibility in future and if required, of converting the post paid numbers, back to the prepaid to which she answered that it can be done easily. So the plan was enabled and my prepaid mobile connections were converted to postpaid and this happened without me moving an inch from my place.
Now when I received the first bill, the cost was around Rs **** /- and due to some medical issues I couldn't contact Airtel to verify the bill value. The second bill most also had a price of around of Rs ****/-, now I contacted Airtel (**-*************) and they agreed on cancelling the plan but when I asked them about converting now post paid mobile numbers to pre paid as it was before to which they replied that it is only possible if I visit the Airtel store physically. I called thrice and all the time, I got the same reply. Now I am worried that in such a pandemic where, there is a lockdown, and most importantly a condition which is highly risky for human lives, how can all the * representatives of Airtel can ask a customer to visit store. It clearly shows the respect Airtel has for human lives and greed for money. Another instance of greed is that when in April the lady called to activate the plan which was also during the peak of Pandemic she didn't ask me to visit anywhere and enabled everything within a day, So in a same way when I asked the representatives to change my numbers to prepaid this time without me moving and they said that they don't have that option and it cant be done. When I asked them to transfer to someone who has an option to change, to which also they didn't help. I asked them to provide me the contact of the lady who enabled this plan for me so that I can write a complaint against her to which the representative said they don't have such record. Really very sorry to know that Airtel doesn't have a system to keep the records/documentations about customers but have a system to keep the records of their bills, again an example of something "" that I don't want to keep repeating. So all my efforts have gone in vain and till now no one from Airtel has taken any step and neither a call back.
I am requesting Airtel to sort out this issue asap and I will be not paying any bill till the issue of mine is not sorted. I will be also copying this email to other people of Airtel as soon as I get the information and as per the response of Airtel. Also, in future, if I continue Airtel I would request Airtel people or third party to never call me with any offers as most of the time what is promised is not delivered. You are free to disconnect the service and we will be happy to move to another vendor.
Now I want the refund and my Airtel postpaid mobile numbers to be converted to prepaid without asking me to travel.