Mobile device zooming with 2 y-axes

[chrissyheb]

Hello,
I have a application where I have to use two y-axes. If I use the graph on my laptop and zoom in with the mouse, I can click and hold to zoom and both y-axes are showing exactly the area I marked.
If I view the same graph on a mobile device (tried with chrome on iPad (current iOS version) and brave/firefox on Android 9.0) and try to zoom in only the left (main) y-axis zooms in, the right one keeps its scale.
Can anyone please give me a hint how to achieve the same behaviour on a mobile device as it is with a desktop browser?
Thanks a lot.
Chrissy

Initialization is done by following code.

labelsDiv: 'legend_div',
legendFormatter: legendFormatter,
animatedZooms: true,
title: '',
legend: 'always',
labels: ['time','y1Val1','y1Val2','y2Val1','y2Val2'],
xlabel: 'time',
ylabel: 'Y1',
y2label: 'Y2',
includeZero : true,
drawAxesAtZero : true,
xRangePad: 1,
series: {
    'y1Val1': {
        color: 'blue',
    },
    'y1Val2': {
        color: 'green',
    },
    'y2Val1': {
        color: 'red',
        axis: 'y2',
    },
    'y2Val2': {
        color: 'orange',
        axis: 'y2',
    },
 },
 axes: {
    x: {
        pixelsPerLabel: 40,
    },
    y: {
        valueRange: [-10,11],
        pixelsPerLabel: 20,
    },
    y2: {
        valueRange: [0,367.5],
    },
}