sql server 2005 - There is already an open DataReader associated with this Command which must be closed first SQL Reporting Services -

i getting 'already open datareader associated command must closed first'. have enabled mars still error. i'm using sql server 2005 , i'm doing within report.

below code:

insert [ins data collection files].dbo.[orders missing seats] (insuser,ordernumber, reference, seat, processdate)  (select    distinct 'frc16',[ins data files].dbo.[mes queue detail].ordernumber, [ins data files].dbo.[mes queue detail].reference,                                            [ins data files].dbo.[mes serial parts].partnumber,  [ins data files].dbo.[mes queue detail].processcompletetime         [ins data files].dbo.[mes serial parts] inner join                   [ins data files].dbo.[mes queue detail] on [ins data files].dbo.[mes serial parts].insuser = [mes queue detail].insuser ,                    [ins data files].dbo.[mes serial parts].serialnumber = [ins data files].dbo.[mes queue detail].serialnumber      ([mes serial parts].insuser = 'frc16' , [mes queue detail].insuser = 'frc16' , [ins data files].dbo.[mes serial parts].partnumber <> '*notrequired')  , ([ins data files].dbo.[mes serial parts].parentserialnumber = 0) ,                    ([mes queue detail].mesqueuename = 'finalver') , ([mes queue detail].processcompletetime > '1/1/1900 12:00:00 am') ,                    ([mes serial parts].actualpartserialnumber = 0) , (left([mes serial parts].partnumber, 3) not in ('3lh', '3rh', '2ct') , [ins data files].dbo.[mes queue detail].processcompletetime not in (select processdate [ins data collection files].dbo.[orders missing seats] )))