vba excel - macro executes only when sheet is active

A function creates banded rows on another worksheet. The routine only seems to work when the sheet is active, so I believe the statement nomenclature is incorrect. I've tried setting the worksheet reference but the function does not work regardless if I set it within the function, within the sub, or both. Can someone point me in the right direction on how to deal with calling a function? I want the sub to work regardless what sheet or workbook the user has active.

Public Sub Band()
    Set wb = ThisWorkbook
    Set ws = wb.Sheets(1)
    With ws
         fRow = .Cells(Rows.Count, 1).End(xlUp).Row
         eRow = fRow
               BandRows_Fm 54, eRow
    End With
End Sub

Private Sub BandRows(StartRow As Integer, EndRow As Integer)
    
    Range("B" & StartRow & ":J" & EndRow).Interior.ColorIndex = xlNone
        
    For i = StartRow To EndRow
        If Not Rows(i).Hidden Then
            nohide = nohide + 1
                If Not nohide Then
                    Range("B" & i & ":J" & i).Interior.Color = RGB(225, 225, 225)
                End If
         End If
    Next i
End Sub

Thank you Norie. Exactly what I was after.