I have two worksheets where I am wanting to match data on tab 1 to data on tab two and return the intersecting value. I am using the formula below and keep returning the value of 0?

=IF(ISERROR(INDEX(Citrus!$A$1:$I$539,MATCH(A5,Citr us!$A$1:$H$296,0),MATCH($D$1,Citrus!$A$1:$Z$1,0))) ,0,INDEX(Citrus!$A$1:$I$539,MATCH(A5,Citrus!$A$1:$ A$296,0),MATCH($D$1,Citrus!$A$1:$Z$1,0)))

What am I doing wrong?