Realme - Device Color is changing from bottom left day by day

I am using realme * Pro which screen has some minor scratches which gets around *-* months ago. On *nd July My phone screen color is changing from bottom left and it is increasing day by day. I raised a complaint regards this but there is no response regards my complaint. I have register *-* complaint but still there is no response i called customer care executive but they are not helping me. They daily said that you will receive a call with **-**hrs. After few days phone screen is totally unable to view any thing because the screen is black everywhere. After ** days one of the complaint status is updated but till then Device is unable to control then its fingerprint and vibration also stopped working after this incident. And now device in service center Noida they said that you have to pay screen charges around ****rs. but its color is not changing because of me, and its not get black because of me. At now they are not ready to repair my phone.