If(AND) combination produces “You’ve entered too many arguments for this function” error

I am struggling to find the missing piece to a formula based on two dropdowns with both having the ability to include all the criteria. Can some evaluate this for me?

=if(and(D6="All",D8="All"),sumifs(GL!$P:$P,GL!$I:$I,D$15,GL!$AB:$AB,$B17),if(D6=All,sumifs(GL!$P:$P,GL!$I:$I,D$15,GL!$AB:$AB,$B17, GL!$R:$R, $D$8)), if(D8=All,sumifs(GL!$P:$P,GL!$I:$I,D$15,GL!$AB:$AB,$B17, GL!$A:$A,$D$6)),sumifs(GL!$P:$P,GL!$I:$I,D$15,GL!$AB:$AB,$B17, GL!$A:$A, $D$6,GL!$R:$R,$D$8))