TL5 lamps don't switch on anymore

[milestone]

Suddenly my 2 TL5 connected to one double EVG don't switch on anymore. I see just one fraction of a second that the light goes on but immediately turns off. When i switch off the power to this EVG for a few seconds the lights will go on again. Mostly i have to try this a couple of times before it really works.
Because these light switching off much sooner then i programmed it I already gave them a new burned in period 100 hour on 100%. But this did´nt solve the problem.
Changing the dimming % didn't work ether
The 2 TL5 lamps are 2 years young. Do I have to replace them already

[Wirus]

The 2 TL5 lamps are 2 years young. Do I have to replace them already

If you ask anyone from aquaristic business they will told you that you should replace the tubes lately after one year ....
However, I suggest the tubes are the problem. If they don´t start and dim correctly, you have to replace them.

[Antipodes]

The 2 TL5 lamps are 2 years young. Do I have to replace them already
Ditto to Wirus!
Fluorescents in the first month lose 20% effectivity and continue to lose effeciency as time goes on.
They are recommended to be replaced 8 mnths to a year, yes this is expensive, but if you got 2 years out of them your have done verrrrry well! (Reason people are moving to LED with 50,000 hrs between replacement).