Toshiba India — Toshiba led tv problem 43u5050

Purchased one TOSHIBA U50 Series 43 inch tv on 19.09.2020, Today the TV switched off automatically and the screen went off . Not switching on and no display is coming .It is fully black. I have promotioal offer of 4 years warranty for my tv as i have purchased TV on 19.09.2020. The promotional offer was given for the purchase period of 18 to21 sep 2020. I want to claim the warranty offer. I have attached the special warranty offer with this Kindly do the needful .
But ur Toshiba led service division is asking the soft invoice copy of my product..i couldn't get/download it..
Kindly instruct them to check my TV's real problem..

In their first visit they told that it was a panel problem..how they are telling that the board is having problem..
What is the necessary of that invoice softcopy?

They are totally making me frustrated condition.

Regards,
MURUGAN S