I have written the following formula, but an #N/A value is being returned.

=SUMPRODUCT(--(YTD!$B$2:$B$65536={"*7*","*16*"}),--(YTD!$AB$2:$AB$65536))

I am trying to sum the cells in column AB where the cell in column B
contains either a 7 or a 16.

Please could someone advise if I need to make a correction to the existing
formula, or if I should be using a different function altogether.

Many thanks in advance.