dear i think the laser tube died.usually the power loss gradually but suddenly no power at all.So you had better to change a new 100W laser tube.I think i can help you with good quality laser tube.Rated power 100W Max power can reach to 120w.Last time one customer like you in this forum already bought one tube from me.He is very satisfied with our quality.Canton Wonder Laser Technology Co.,Ltd - Canton Wonder Laser Technology Co.,Ltd