Warranty for Hisense TV

I logged call with the shop for Hisense to repair my 65inch TV under warranty as the screen is on but these no pictures, after a week of follow up, I called and was told they are waiting for the shop to send the invoice and picture of the TV. still waiting for the Technician to come, what one needs to do for a TV to be fixed as it's under warranty, Hi-fi Corp still has no answer.