need axis independent of data / yaxis.setExtremes has no effect

In my mixed line/column chart with two y-axes

I have tried many combinations of
yaxisDrop.setExtremes(0, 1, false, false);
yaxisDrop.setMin(0); yaxisDrop.setMax(1);
yaxisDrop.setMaxPadding(0); …

and orders in time (before, after adding data series)

but the max and min numbers on yaxisDrop
are always automatic / different dependent on data.

Is there no way to set them fixed?

Hello all,
I’ll attach a picture to make my pain clearer:
the left y-axis shows a time value - should not be negative, right?
the right y-axis show a dropout percentage - should not be greater than 100% , right?

But depending on which data points are added, the axes somtimes(!) get nonsensical.
Any ideas how this come or what to do?
Best regards, Daniel

p.s.: setExtremes works only as long as pass values which are far greater than data points.
But when data points get near the “setExtreme-values” the latter are ignored.
19407.png