Excel VBA graph based on Series not working properly

Question

I'm using the following VBA code in Excel in order to produce 2 graphs with a data picked up from the sheet and slightly elaborated. As I'm not using ranges directly for the graphs and need to use arrays for X and Y axes, I decided to go for Series. X has Date type and Y has Integer type. First it worked, but then the graphs started giving me wrong data, something random coming directly off the sheet. I suppose there could be something wrong in the way how the charts are declared. Here's the code, what could go wrong with it?

Dim crt1, crt2 As Chart 
Dim sr1, sr2 As Series

ActiveSheet.Shapes.AddChart2(201, xlColumnClustered, 60, 50).Select
Set crt1 = ActiveChart
Set s1 = crt1.SeriesCollection.NewSeries()
sr1.Values = dataArray1
sr1.XValues = datesArray1

ActiveSheet.Shapes.AddChart2(332, xlLineMarkers).Select
Set crt2 = ActiveChart
Set s2 = crt2.SeriesCollection.NewSeries()
sr2.Values = dataArray2
sr2.XValues = datesArray2

This problem also persists when I comment the code for the second graph.

P.S. Excel says "Runtime error 424. Object required" underlining "sr1.Values = dataArray1" and then "sr1.XValues = datesArray1"