My Father's Z Flip 4 of 256 GB Variant suddenly appears green line on main screen and cover screen is working properly. It has no physical damage on main or cover screen still this happens . Can any tell how it is possible If any one wants photos of ...

I have many samsung devices like Galaxy Tab A9+ and Galaxy F34 5G and many more but I am facing this green line issue in my Galaxy A31. So if any one can help me in this please help me