sql - error- Each column has to have a unique name when you’re returning the query -

i trying run reporting services below sql query

select ca.callingpartynumber, ca.originalcalledpartynumber, case when calledpartylastname not null ca.calledpartylastname + ',' + calledpartyfirstname  else p1.name end, p1.location, p1.dept, p1.title, case when callingpartylastname not null ca.callingpartylastname + ',' + callingpartyfirstname  else p3.name end calldata.calldetailreport ca join ps_bc_peoplesource_base p1 on ca.originalcalledpartynumber = replace(p1.bc_int_phone, '-', '') left outer join ps_bc_peoplesource_base p3 on ca.callingpartynumber = replace(p1.bc_int_phone, '-', '') originalcalledpartynumber in (select replace(bc_int_phone, '-', '') internal_modified  ps_bc_peoplesource_base bc_lan_id = 'f7c') --and datetimedisconnect between @startdate  , @enddate --1221 

i error-

“an item same key has been added.”

you missing column alias 2 case statement in select query. ssrs uses column name key, not table + column, choking.

refer here , here , here also

select ca.callingpartynumber, ca.originalcalledpartynumber,      case when calledpartylastname not null               ca.calledpartylastname + ',' + calledpartyfirstname           else p1.name end calledpartylastname,     p1.location,      p1.dept,      p1.title,     case when callingpartylastname not null              ca.callingpartylastname + ',' + callingpartyfirstname          else p3.name end callingpartylastname     ...     ...