Sansui India — I'm complaining about JUST (jitna do utna lo) offer

On 19/01/2016, I purchased a sansui led tv model no. SMC40HB21C under the JDUL offer. According to the offer I was eligible to avail 20700/- redemption on the next purchase of any KAIL Limited product at the end of 4 years 11 months from the date of current purchase.
Now at the end of the holding time period when I contacted the dealer to avail the offer, he said the company has shut.

I have tried to open the website www.sansui-india.com mentioned in the certificate that was provided to me at the time of purchase, it's not functional and tried to call customer care number ([protected]) also mentioned in the certificate but it's not working too.

I've no clue what to do now. Could you please suggest and help me in this regards.

Thanks