DIAGNOSIS The curved screen has a standard matte anti-glare coating. Using wrong cleaners will create permanent smears or strip the coating.
FIX Power off the monitor. Use a dry, soft microfiber cloth. Gently wipe in one direction along the curve. For fingerprints, lightly dampen a second microfiber cloth with distilled water only. Wipe gently, then immediately dry with the first dry cloth.
IF THAT DIDN'T WORK For stubborn spots, use a monitor-specific cleaning spray. Spray a tiny amount onto the microfiber cloth, never directly on the screen. The curve means liquid can pool at the edges. Be careful.
HEADS UP Never use window cleaner, alcohol, ammonia, or abrasive cloths. These will permanently haze the anti-glare coating. The damage is not repairable.