What's wrong with my Marineland Double Bright LED fixture??

[Timbits]

Nono guys sorry my post might have been confusing,

Let me try again,

1.Timer goes on,
2.Light still off.
3.5 hrs later ............ Light goes on
4.Timer turns off
5.Light turns off.

Strange eh? Light was working perfectly fine before and it's NOT the timer, I have another light on the same timer and that ones fine.

And I do have a mechanical timer not digital.