Data Validation with Index Match

You could use:

=IFERROR(INDEX($B$3:$C$20,MATCH($D$2,$A$3:$A$20,0),MATCH($E$2,$B$2:$C$2,0)),"")

or given numeric output

=IFERROR(SUMIF($B$2:$C$2,$E$2,INDEX($B$3:$C$20,MATCH($D$2,$A$3:$A$20,0),0)),"")

former more flexible in terms of output data type