MY LED LIGHTS WON'T TURN ON!

Ugh, these is so frustrating! I have my led lights under cabinets LED lights to work, but they just won't switch on. I've looked the fixtures - they seem fine. Maybe the circuit breaker is {the{ problem? I can't know what else to try! Any suggestions would be much appreciated! Identifying Faulty LED Lights When your LED lights start to act up,