ObservableCollection causing a lot of GC Pressure

Question

I am using Livecharts2 in my WPF Application in order to show a realtime graph (100 data points/s)

The chart is connected to an ObservableCollection. I found that my Code to add DataPoints is causing a lot of GC Pressure:

The Code to add Data is as follows:

// amount of datapoints to keep in chart per series 
// (200 points / 25points per second = 8 seconds)
static int dataLength = 200;
// 4 series in total
private static List<ObservableCollection<ObservableValue>> seriesDataPoints 
    = new List<ObservableCollection<ObservableValue>>();
private static List<string> seriesNames = new List<string>();
// variable in attempt to reduce GC pressure
private static ObservableValue ReUseShell = null;
// add new datapoint (and remove old datapoint if series > dataLength )
public static void AddDataPoint(double point, string seriesName)
{
    // search for the correct series
    int seriesIndex = -1;
    for (int i = 0; i < seriesNames.Count; i++)
    {
        if (seriesNames[i] == seriesName)
        {
            seriesIndex = i;
            break;
        }
    }
    // series was not found, create new serries
    if (seriesIndex == -1)
    {
        seriesIndex = CreateNewSeries(seriesName);
    }
    // check if we have a reusable datapoint (in order to reduce gc)
    if (ReUseShell != null)
    {
        ReUseShell.Value = point;
        seriesDataPoints[seriesIndex].Add(ReUseShell);
        ReUseShell = null;
    }
    else
    { // we dont have a empty data point (series < datalengt / ~initialisation)
        seriesDataPoints[seriesIndex].Add(new(point));
    }
    // remove oldest datapoint and reuse it for the next data fill
    if (seriesDataPoints[seriesIndex].Count > dataLength)
    {
        ReUseShell = seriesDataPoints[seriesIndex][0];
        seriesDataPoints[seriesIndex].RemoveAt(0);
    }
}

and this is how the chart looks:

Is there any issue with my code / Observable collection or does the issue reside with the Library LiveCharts2?