Tata Teleservices — Invoice generated even after request to terminate service

Address:

Pune

I had requested to terminate their internal services in March 2020. Initially they told me to clear current bill and they will terminate.
I paid that and asked them to terminate.
They did not respond further on this for months. No answer to customer care call or mails. Meanwhile the system kept generating invoices.
Now yesterday their legal team have sent me a mail asking to pay within 2 days. Here also they gave a phone number, which no one answered.

I had been following up with them for more than 6 months and they did not respond. Initially they told me due to Covid there will be some delay and they will process the termination request.

As a customer, I am being invoiced for their incapability to process requests on time. Also totally no response from their customer care team as well as their head.