Runtime error trying to move col from one location to another.

Hi, i am enclosing a test file.

I am trying to move column AD in-between cols 7 and 8.

I have this code.......but it does not seem to work. I thought i had used something like this before and it worked but for some reason i cant figure it out. Any thoughts?

Sub test()

Dim fl_name As String

fl_name = ThisWorkbook.Name

Set inputfileworksheet = Workbooks(fl_name).Worksheets("Quality Compliance")

last_row_in_study_col = 169
Study_Col_number = 30

inputfileworksheet.Columns(Study_Col_number).Resize(last_row_in_study_col, 1).Cut
inputfileworksheet.Columns(8).Resize(last_row_in_study_col, 1).Insert Shift:=xlToRight


End Sub