Reasons: 1. Haven’t shake absolutely before use; 2. Aerosol can body incline angle too large during use, which makes the spraying with too much gas and dilutes the paint; 3. surrounding temperature too low and poor ventilation; 4. Spray too thick for the first time. How to use: 1. Use under room temperature; 2. Master the right use method; 3. Avoid upside-down spray and inclined spray; 4. Avoid using in overcast and rainy, humid, freezing weather.