Using subtotal function in Excel

[target_21]

When I try to subtotal, I get this error (see my snip below).  I have been using subtotals for over a decade and now this ridiculous warning, any ideas?

Of course I can copy all my data to a new spreadsheet and the error goes away but I am tired of doing this constantly.

[#2]

@target_21 

Try selecting all rows below the last row of data.

On the Home tab of the ribbon, click Clear > Clear All.