Iphone white blank screen.. HELP!

A few months ago, i took my iphone 13 pro max to an authorized apple service provider for fixing and they got my phone replaced with a new one since it is under warranty. A few months later, the replaced phone started having problems. The screen started showing white lines and then suddenly it just went blank white with no other functionality visible on the screen. it is just white blank screen. I took it back to the authorized apple service provider but now they have advised i pay $2K for replacement since warranty has expired. I need to contact apple support center to let them know about this but i cant see any live chat