For iPad horizontal picker is not horizontal at portrait orientation

[dsenash]

Hi,
I am doing application for iPhone and Ipad. For iPhone everything is correct with HorizontalPicker. For Iphone7 plus as well (similar as iPad realization of split view.)
For iPad I got something amazing.
Landscape is good. Portrait is wrong.
See screenshots:

Code about HorizontalPicker is so small:
// MARK: - HorizontalPickerViewProvider

func numberOfRowsInHorizontalPickerView(_ pickerView: HorizontalPickerView) -> Int {
    return titles.count
}

func horizontalPickerView(_ pickerView: HorizontalPickerView, titleForRow row: Int) -> String {
    return titles[row]
}

func horizontalPickerView(_ pickerView: HorizontalPickerView, didSelectRow row: Int) {
    horizontalMarker = row
    showGraph()
}

func useTwoLineModeForHorizontalPickerView(pickerView: HorizontalPickerView) -> Bool {
    return true
}

func textColorForHorizontalPickerView(pickerView: HorizontalPickerView) -> UIColor {
    return UIColor.darkText
}

func pickerViewShouldMask(pickerView: HorizontalPickerView) -> Bool {
    return true
}

Below is screenshot of Picker's constraints. It is inside View.

Any ideas why?

Rg, Dmitry