Substitute Function in Excel VBA for cell range

Try this. Note that it uses the VBA Replace function, so you need to rename your 'Replace` subroutine.

Sub ReplaceText()

    For Each c In Sheets("Sheet1").Range("A1:A629").Cells

      c = Replace(c.Value, ",", ";")

    Next c

End Sub

Note: This will only work if you have values in the cells, no Formulas. Because Excel has a formula length limit of 1024 characters. But given you have this specific error, your cells must not be formulas.

Try this

Sub Replace()

    Dim rng As Range, cell As Range
    Set rng = Sheets("Sheet1").Range("A1:A629")

    For Each cell In rng
        cell = WorksheetFunction.Substitute(cell, ",", ";")
    Next
End Sub