Samsung — Screen bleeding without any physical damage..

My mobile samsung galaxy m31 start bleeding without any type of physical damage.
I call to customer care he told me to it may be a software problem you have to reset your phone. N j have done reset my phone, then also my problem doesn't solve then he say it may be hardware problem you have to visit service center.
I go to service center I have shown my phone they said me you have to change your display n price will be 5, 350. How can I give this much of money. If there is my no fault.
I have called customer care lots of time but no one helps me.
My phone Warranty date is over just before 1 month n I'm didn't take any claim.
We trust on Samsung products but you people break our trust.
So I have complaint against samsung quality.