how to get correct coordinate in axis?

I’m developing chart with sci chart. And I current make candle stick chart.

I want to get correct center coordinate from user’s touch location.

so, I tried this way.

1. get touch location
2. get axis data from touch location like this
3. get coordinate from data

let location = gestureRecognizer.location(in: self) // type is CGPoint
let selectedDate = xAxis.getDataValue(Float(location.x)) // xAxis's type is ISCIAxis
let selectedPoint = xAxis.getCoordinate(selectedData)

If I do that, no matter how far to the right you touch from the center line of the candlestick, you will get the position of the left candlestick.

If the candlestick center line is not crossed, the left data is unconditionally obtained.

I want to get the data closest to the touch, how do I do that?