If the light is blinking on and off (o x o x o x) This is a hardware problem either with the light itself or the switch it is connected to. (if you upgraded from an incandescent light, they may have been using a switch designed for incandescent lights only)
If the light is changing colors rapidly (a b c d e f) this is the 'mardi gras' mode on the color logic light. It should change to the next mode normally, by turning the light off and back on within 10 seconds. Turning the light off and back on after 10-14 seconds resets the light to color mode #1. If neither of those gets it out of this mode, it's time to get some warranty work done.