Formula getting #value error. Can't detect how to fix.

I have written the below formula and it is coming up with a #value error. I traced the errors and the data format match's all other cells. I can't figure out what I need to do to resolve this error. Any Help, please.

=SUMPRODUCT(--(employee_name=A4),--(date>=B4),--(date<=C4),--denomination)

Defined Names:
employee_name = =March:August!$B$3:$B$600
date = =March:August!$D$3:$D$600
denomination = =March:August!$C$3:$C$600

Error:
See Attachement