How to clean the LCD screen of the camera.
To clean the LCD of the camera, wipe the screen using a microfiber cleaning or soft damped cloth. Do not use any solvents or liquid-based cleaners. Using these substances may cause the LCD screen coating to peel off. A microfiber cleaning cloth will remove dust, dirt and fingerprints from the LCD screen without scratching or streaking and without the use of harmful chemicals.
NOTE: A cleaning cloth can be purchased from any camera specialty store or ordered directly from the Sony® Store.
Please contact a local or online authorized retailer to purchase a Sony product.
For customers in the United States: https://www.sony.com/retailers
If the issue is still unresolved, the product need to be repaired.  Go to Product Repair.