Resistance to botrytis cinerea varies from place to place, so it is suggested to use pesticide components alternately, such as fludioxonil, iprodione, Trichoderma, procymidone, eugenol, boscalid or azoxystrobin (be careful with melons in azoxystrobin). You have to take drugs all over your body.
Humidity should be controlled in protected areas, and fungicidal aerosol such as procymidone can be used in rainy days.
Seriously diseased fruit, the diseased leaves are wrapped in plastic bags and taken out early.
Prevention first, comprehensive prevention and control. Use pesticide ingredients alternately, and don't use the same pesticide ingredients continuously. This is the principle of plant protection.