The clock ran initially wrong, but it was more on the not-understood operating instructions.
(Please clock reset rephrase, or add the calibration of the pointer when set to 12th
CLOCK reset (calibration of the pointer to 0 clock):
S1 press the button repeatedly until the second hand (approximately from 11: 30h) Step by step the 12am reached (set to 12).
Slow ran keys to all pointers to DOT 12am stand, then press S2 button.
It does not make it, the clock is wrong.
Stop light and get it calibrated, now has a top clock that shows the correct time.
(I almost gave up, stupid instructions ...)