Code to Change Y-Axis not firing anymore Excel VBA

[theteerex]

My code for changing the Y-Axis was working perfectly yesterday yet does nothing today.
It monitors the minimum and max values in static cells and changes the scale based on the code below.
I know the change event is the correct one as it was working yesterday.
Could I ensure that it always runs without resorting to using a button?
There is no error message either when I run it.

Option Explicit
            Sub ChangeAxisScales_Calculate()
               Dim objCht As ChartObject
               For Each objCht In Sheets("Price Bridge Chart").ChartObjects
                  With objCht.Chart
                     ' Value (Y) Axis
                     With .Axes(xlValue)
                        .MaximumScale = ActiveSheet.Range("L34").Value + 2000000 
                        .MinimumScale = ActiveSheet.Range("K34").Value - 2000000 
                        MsgBox "Max = " & .MaximumScale [COLOR=#008000]'- For Error Checking[/COLOR]
                        MsgBox "Min = " & .MinimumScale [COLOR=#008000]' - For Error Checking[/COLOR]
                        .MajorUnit = 250000 'Chart horizontal lines
                        End With
                  End With
               Next objCht
            End Sub