Run-time error '1004'

Hello All,

I am trying to modify Peltier's excel vba graphing code to fit my needs. However, I keep getting a run-time error '1004' on ".Values = rngChtXVal1.Offset(irow - 1, 0)"

Can anyone tell me what I've missed?

Sub Multi_Range_Chart()
    Dim Cored_Wells As Integer
    Dim Current_Well As Integer
    Dim myChtObj As ChartObject
    Dim rngChtData1 As Range
    Dim rngChtData2 As Range
    Dim rngChtData3 As Range
    Dim rngChtData4 As Range
    Dim rngChtData5 As Range
    Dim rngChtData6 As Range
    Dim rngChtXVal1 As Range
    Dim irow As Long
    
        
    Current_Well = 1
        
    Cored_Wells = Application.InputBox(Prompt:="How many cored wells?", Title:="Multi Well Graphing Untility", Default:=1, Type:=1)
    If Cored_Wells = 0 Or Cored_Wells < 0 Then
        Exit Sub
    End If
        
    Do Until Current_Well = Cored_Wells + 1
        Set rngChtData1 = Nothing
        On Error Resume Next
        Set rngChtData1 = Application.InputBox(Prompt:="Select range of cored well #" & Current_Well, Title:="Multi Well Graphing Utility", Type:=8)
        On Error GoTo 0
        If rngChtData1 Is Nothing Then Exit Sub
                                
        ' add the chart
        Set myChtObj = ActiveSheet.ChartObjects.Add _
            (Left:=250, Width:=375, Top:=75, Height:=225)
        With myChtObj.Chart
        ' make an XY chart
        .ChartType = xlXYScatterLines
        ' remove extra serious
        Do Until .SeriesCollection.Count = 0
                .SeriesCollection(1).Delete
            Loop
        End With
        
        Select Case Current_Well
        
            Case 1
        
                ' define chart's X values
                With rngChtData1
                    Set rngChtXVal1 = .Rows(1).Offset(0, 1).Resize(.Columns.Count - 1)
                End With
                With myChtObj.Chart
                    ' add series from selected range, column by column
                    For irow = 2 To rngChtData1.Rows.Count
                        With .SeriesCollection.NewSeries
                            .Values = rngChtXVal1.Offset(irow - 1, 0)
                            .XValues = rngChtXVal1
                            .Name = rngChtData1(irow, 0)
                        End With
                    Next
                End With
            Case 2
                Exit Sub
            
            End Select
    Current_Well = Current_Well + 1
    Loop

End Sub

When the error occurs and you DEBUG, type this in the Immediate Window (Ctrl-G) and see what the current value is:

? rngChtXVal1.Address

Thank you JBeaucaire. That is exactly what I needed so I could properly debug my code. I found out that I was missing the comma in the .Resize property a few lines up which was eventually causing the error. Thanks for the response, so here is some rep!