Excel VBA Loop Every Chart and Every Series and Change Y Values

Hello,

I am trying to change the Y values of every chart in my worksheet. I have many, many charts each with 3 series named "Data", "Min" and "Max".
Each chart is named "C3", "C4", etc.
If the series name is "Data" I want it to grab the information from sheet "Summary" from columns L to AO for the row number of the Data double and same can be said for Min and Max.

Here is what I have:

Dim Data As Double
Dim Max As Double
Dim Min As Double

Dim mySeries As Series
Dim seriesCol As FullSeriesCollection
Dim I As Integer

For k = 3 To NumOfChtsPlusTwo
    I = 1
    Data = k + 15
    Max = 129 + 3 * k
    Min = 128 + 3 * k
    Set seriesCol = ActiveSheet.ChartObjects("C" & k).Chart.FullSeriesCollection
    For Each mySeries In seriesCol
            Set mySeries = ActiveSheet.ChartObjects("C" & k).Chart.FullSeriesCollection(I)
            If mySeries.Name = "Data" Then
                mySeries.Values = _
                    "='Summary'!$L$ & Data & :$AO$ & Data"
            ElseIf mySeries.Name = "Max" Then
                mySeries.Values = _
                    "='Summary'!$L$ & Max & :$AO$ & Max"
            ElseIf mySeries.Name = "Min" Then
                mySeries.Values = _
                    "='Summary'!$L$ & Min & :$AO$ & Min"
            End If
            I = I + 1
    Next mySeries
            
Next k

I am getting Run-Time error '1004': Application-defined or object-defined error