Micromax - Replacement not done

Dear Sir/Madam
I want to raise an issue regarding the replacement of my **inch uhd tv. Since September **** I have been complaining to the customer service executives of Micromax, concerned persons responsible (Mr. Kundan, an Micromax official based at Patna) as well as the service providers (Ujala Enterprise, Purnea, Bihar) who was dealing with the case, about the technical issue that has occurred on my TV.
After a number of phone calls and emails, the service provider paid a visit and promised me to do the possible arrangements. Later, after re-scrutiny and collecting the necessary information and photographic evidence by the service provider, dated ** Dec ****, Mr. Kundan came up with the assurance that I will be receiving a replacement of my complaint with a short period. That communication was made way back in January ****.
After the assurance also, my case was closed multiple times and I had to re-register it up afresh (more than **-** times). The last complaint was last raised on **th December **** (I suppose). More than a dozen dates for replacement was committed by Kundan ji and the service provider and to my sorry, all dates elapsed.
The case was later handed over to the Escalation department of Micromax, where I talked with Ms. Pooja Madam. She too gave me multiple dates of delivering the product. But, unfortunately, this didn't happen.
The current update is that customer service executives say, "...your complaint is closed. There is a technical problem with your Awb number. Mr. Kundan stopped receiving my phone call. The service prover is nonetheless the same.
In WhatsApp communication, Mr. Kundan still sticks to the point that I will be receiving the replacement but I don't see any movement. Off late, he has stopped replying to my messages too.
Now, provide me the assistance on what to do. I have been fighting this battle for the last ** months with ** months of false promises and assurance. Technically, I meet all the conditions prescribed by Micromax to get a replacement.
What to do?