How Can I Solve The Following Pl/Sql Queries Properly? In The Following Queries Last Month Count Is Not Correct.How Can I Solve This Issue?

with t as
                    ( SELECT cwd_group_par.id as project
                    , cwd_group_par.group_name as project_name
                    , case
                    when TO_CHAR(chgroup.created,'YYYY-MM-DD') >= '2015-06-24' AND TO_CHAR(chgroup.created,'YYYY-MM-DD') <= '2015-06-30' then 'LASTWEEK_COUNT'
                    when TO_CHAR(chgroup.created,'YYYY-MM-DD') >= '2015-06-01' AND TO_CHAR(chgroup.created,'YYYY-MM-DD') <= '2015-06-30' then 'LASTMONTH_COUNT'
                    when TO_CHAR(chgroup.created,'YYYY-MM-DD') >= '2015-07-01'AND TO_CHAR(chgroup.created,'YYYY-MM-DD') <= '2015-07-07' then 'CURRENTWEEK_COUNT'
                     end as tm
                    , count(distinct i.id) cnt
                    from jira.jiraissue i
                    join jira.cwd_membership cwd_mem on i.assignee =  cwd_mem.lower_child_name
                    join jira.cwd_group cwd_group_par on cwd_group_par.lower_group_name = cwd_mem.lower_parent_name
                    join jira.issuestatus on i.issuestatus = jira.issuestatus.id
                    JOIN jira.PROJECT ON i.PROJECT = jira.PROJECT.ID 
                    join jira.changegroup chgroup on i.id = chgroup.issueid
                    join jira.changeitem chitem on chgroup.id = chitem.groupid 
                    where cwd_group_par.id in("+str(projectids)+"
                    )
                    and issuestatus in (6 
                         )
                    AND jira.PROJECT.PKEY = 'ISD'
                    AND chitem.field = 'status' and to_char(chitem.newstring) in ('Closed')
                    
                    group by cwd_group_par.id, cwd_group_par.group_name
                    , case when TO_CHAR(chgroup.created,'YYYY-MM-DD') >= '2015-06-24' AND TO_CHAR(chgroup.created,'YYYY-MM-DD') <= '2015-06-30' then 'LASTWEEK_COUNT'
                    when TO_CHAR(chgroup.created,'YYYY-MM-DD') >= '2015-06-01' AND TO_CHAR(chgroup.created,'YYYY-MM-DD') <= '2015-06-30' then 'LASTMONTH_COUNT'
                    when TO_CHAR(chgroup.created,'YYYY-MM-DD') >= '2015-07-01' AND TO_CHAR(chgroup.created,'YYYY-MM-DD') <= '2015-07-07' then 'CURRENTWEEK_COUNT'
                    end 
                    )
                    select * from t
                    pivot
                    ( sum(cnt) as wk
                    for tm in ('LASTMONTH_COUNT','LASTWEEK_COUNT','CURRENTWEEK_COUNT')
                    )
                    order by 1;