A milky white haze is a rare occurrence. It usually occurs on dark colors where Clear Prep+Finish™ was applied too thickly and / or over-worked as it began to dry.
The Solution: Wet a sponge or rag with water, and gently scrub the surface to thin the finish. You can also try rubbing alcohol. If this does not correct the haziness or starts to strip color, simply apply more color or a glaze (mixture of color and Clear) as your final topcoat. Even the tiniest drizzle of color in the clear finish will correct the haze.