Do I use SUMIF or SUMPRODUCT

Im having a lapse in memory. I cant remember how to sum a matrix with a conditional for both the column header and rowname. Example attached. heres the description. I have row with several values for months (jan feb, etc as each header) however some repeat. I also have a list of names in the first column, some of which repeat. I need the function to add up the number of hours worked for a particular person for a particular month. Thanks!