Tata Sky Broadband — Promised Waiver rental on unavailability service not provided

My Consumer number is C[protected].

I have recharged my plan on 28th April 2020 with 180 days plan with additional validitty of 60 days as an offer. The date plan validity started. Due to issue in connection the internet did not work for 40 days and customer care told they will restart the validity once it starts working. The connection has been restored after 40 days after repeated complaint.
But the validity and waiver not received as promised over call. Tatasky charged for 40 days even though service was not provided.