Colour floating occurs because the granule size, shape, density, and dispersion of the pigments are different, the pigments in the top layer and under layer disperse unevenly resulting in a colour difference between layers.
Common Cause
Colour floating relates closely with pigment convection during the formation process of paint finishes, thus incorrect manufacturing formula and technique are the main reason for this paint defect.
Repair
Re-spray the area with a quality paint over the defected paint finish.