c# - Report Builder not showing IIF result -

i'm trying modify report builder report (visual studio 2013) , it's not displaying 4 expressions. following field coded , works great!

=first(microsoft.visualbasic.interaction.iif(fields!ispass.value = "y", "yes", "no"), "dataset1") 

however, have 4 other fields coded same way different field values this:

=first(microsoft.visualbasic.interaction.iif(fields!issuccessful.value = "y", "yes", "no"), "dataset1") 

that don't display "yes" or "no". in particular field, supplying "n". here rb snipit pass expression works great:

and here portion of pdf report:

here data looks fields i'm having issue (don't worry misspelling on exceptional, misspelled everywhere , isn't issue):

here c# code used populate xsd file:

if (result.any()) {   foreach (var item in result) {     dtresult.rows.add(new object[] {       item.fullname.toupper(), item.storenum, item.ssid, item.evaldate,       item.evalyear, item.isexeptional, item.ishighsuccess,       item.issuccessful, item.isunsuccess, item.ispass,        item.justification, item.overalperformance,item.supercomment,       item.curmanager.toupper(), item.emptype, item.questionno,       item.questiondescript, item.questionshorttitle, item.questionpass,       item.questioncomment     });   }  } 

and here xsd layout:

i know isn't going easy figure out what's wrong, watching data provide report looks fine. if no 1 has ideas, guess have rewrite thing in crystal reports , go there (??).

just elimination process, have tried dumping out field values instead of using expression, make sure data getting passed report how expect be?

it looks it's dataset issue. try creating table , adding fields dataset dragging them onto it. should able see coming dataest.