Add Cell Comment With Text

if choose a cell then the code works fine, but when i choose a selection of cells
(ex. A1 A2A3 A4) then the code fail to excute in this line: Invalid proceduer call or argument error

.AddComment "hmk :" & Chr(10) & " value was " & ActiveCell.Value

and then fail to excute in this line: typr mismatch error

Selection.Value = (Selection.Value) * r

now here, does have to be loop to solve

here is the full code

Sub test()
Dim r As Integer
ActiveCell.ClearComments