Query taking too long to execute and a unbelievable cost-CodePudding

I am currently writing a query and I ran explain to check the query cost and time taken to run it. I observed that the cost is too high after I ran explain. Please find the below query.
create table l1.dm_sc_temp_pl_activity_p as 
select rel,licamt,tcamt, spsc, pdn, pmn4, pcs, clsldt, pci, cpdt, orgtin, bt, pcpldt, slc, sps, pm3, "ln", idt, ddt, rps, df, dat, pz, rpn, pih, pipid, pcpn, psa2, ingdt, incid, uqt, 
acoid||orgid  as orgid, pn, fn, pc, pm5, pm4, rpnpi, pfdt, sfn, catp, pdcs, pm1, st, pl, cltc, cpat, incn, gn, adjsn, clsfdt, acoid, sstp, orgn, sln, sid, drg, rcdt, tel3, pm2, rpsc, pmn3,
acoid||orgid||orgrid as orgrid, alat, inpn, tel2, drgn, pcpidt, acon, pcpid, id, pcpslid, pd, dob, psa1, orgrn, pcpslidt, pcy, pcpsln, pmn2, pmn5, cid, inpid, adjs, pmn1, eldt, empi, pcpfdt, cltp, tel1, pldt, pstn, spn, spnpi, mn, clid, 
efdt, capdt,ssa1,ssa2,sci,sstn,scy,sz,ftsa1,ftstn,ftz,ftci,ad1,ad2,ad3,ad4,ad5,
ad6,ad7,ad8,ad9,ad10,ad11,ad12,ad13,ad14,ad15,ad16,ad17,ad18,ad19,ad20,ad21,ad22,ad23,ad24,ad25,ad26,ad27,ad28,ad29,
adn1,adn2,adn3,adn4,adn5,adn6,adn7,adn8,adn9,adn10,adn11,adn12,adn13,adn14,
adn15,adn16,adn17,adn18,adn19,adn20,adn21,adn22,adn23,adn24,adn25,adn26,adn27,adn28,adn29 
from (
select  
 c.prov_addr1 as ftsa1,
c.prov_state as ftstn,
c.prov_zip as ftz,
c.prov_city as ftci,
c.iscap as rel,
cast(c.claimsvc_billedamt as decimal(18,2)) as licamt,
cast(c.claim_billedamt as decimal(18,2))  as tcamt,
trim(m.id) as id ,trim(m.tel1) as tel1,trim(m.tel2) as tel2,trim(m.tel3)as tel3,
'' as empi,trim(m.gn) as gn,psa1,psa2,pci,pcpldt,pl,trim(mn) as mn,trim(pz) as pz,trim(ln) as ln,
cast(m.dob as date) as dob,'N' as df,m.pcy,trim(m.fn) as fn,m.pcpfdt,m.pstn,
ssa1,ssa2,sci,sstn,scy,trim(sz) as sz,
--dm_prov
case when (trim(p.npi) in ('NULL','NA','')) then '' else trim(p.npi) end as pcpid,
case when (trim(p.npi) in ('NULL','NA','')) then '' else 'NPI' end as pcpidt,
p.lastname||','||p.firstname||' '||p.middlename as pcpn,
-- dm_vend
case when (trim(v.taxid) in ('NULL','NA','')) then '' else trim(v.taxid) end as pcpslid,
v.vendname as pcpsln,
case when (trim(v.taxid) in ('NULL','NA','')) then '' else 'NPI'  end as pcpslidt,
-- level
case when l."HPName"='Aetna Health of California' then '13'
when l."HPName"='Health Net' then '14'
when l."HPName"='Blue Shield of California' then '12'
when l."HPName"='United Healthcare of California' then '15'
when l."HPName"='Cigna for Health Care Professionals' then '16'
when l."HPName"='Anthem Blue Cross' then '17' end as incid,
l."HPName" as incn,
Case
when l."Progdescr"='DHMNSC United Healthcare Commercial' then '30'
when l."Progdescr"='DHMNSC Blue Shield 65 Plus' then '29'
when l."Progdescr"='DHMNSC United Healthcare Canopy Commercial' then '31'
when l."Progdescr"='DHMNSC United Healthcare Medicare Solutions' then '32'
when l."Progdescr"='DHMNSC Blue Shield Commercial' then '28'
when l."Progdescr"  in ('DHMNSC Health Net SmartCare Commercial','DHMNSC Health Net Canopy UC Blue and Gold Commercial',
'DHMNSC Health Net Canopy Care Commercial') then '33'
when l."Progdescr"='DHMNSC Aetna Commercial' then '34'
when l."Progdescr"='DHMNSC Cigna Commercial' then '35'
when l."Progdescr"='DHMNSC Health Net Commercial' then '36'
when l."Progdescr"='DHMNSC Anthem Blue Cross Commercial' then '37'
when l."Progdescr"='DHMNSC Health Net Seniority Plus' then '38'
when l."Progdescr"='DHMNSC United Healthcare Canopy Medicare Advantage' then '50' end as inpid,
case when l."Progdescr"  in ('DHMNSC Health Net SmartCare Commercial','DHMNSC Health Net Canopy UC Blue and Gold Commercial',
'DHMNSC Health Net Canopy Care Commercial') then 'DHMNSC Health Net SmartCare Commercial'
else l."Progdescr"  end as inpn,
'3' as acoid,
'DHMN-SC' as acon,
case when l."LOB" ='M' then '6'
    when l."LOB" ='C' then '7' else '8' end as orgid,
case when l."LOB"='C' then 'Commercial'when l."LOB"='M' then 'Medicare' else "LOB" end as orgn,
case when  l."HPCode" not in ('PGM000295','PGM000294','PGM000333','PGM000332','PGM000326') then '7'  
     when l."HPCode" in ('PGM000295','PGM000294','PGM000333','PGM000332','PGM000326') then '9' else '8' end as orgrid,
case when  l."HPCode" not in ('PGM000295','PGM000294','PGM000333','PGM000332','PGM000326') then 'Non Canopy'  
     when l."HPCode" in ('PGM000295','PGM000294','PGM000333','PGM000332','PGM000326') then 'Canopy' else 'Other MedGroup' end as orgrn,
-- hardcode columns
'3a1bcd23-d88c-4c70-8ffa-267673232647' as pipid,
'Claims' as st,
l."HPName" as sstp,
'DataMart.bak' as sfn,
current_date as rcdt,
current_date as ingdt,
'claimline' as cltp,
'5' as sid,
'Patient ID' as idt,
 -- dm_claim
trim(c.claimno) as cid,
trim(c.seq) as clid,
'Professional' as cltc,
case when (trim(c.billtype) in ('','NULL','NA') or trim(c.billtype) is null)
    then '' else trim(c.billtype) end as bt,
case when (trim(c.claim_fromdate) in ('','NULL','NA'))then null 
    else cast(c.claim_fromdate as date) end as efdt,
case when (trim(c.claim_todate) in ('','NULL','NA'))then null 
    else cast(c.claim_todate as date) end as eldt,
case when (trim(c.claim_recddate) in ('','NULL','NA'))then null 
    else cast(c.claim_recddate as date) end as cpdt,
case when (trim(c.claim_paiddate) in ('','NULL','NA'))then null 
    else cast(c.claim_paiddate as date) end as capdt,
case when (c.claim_netamt::decimal(18,2)='0' and c.iscap='1') then cast(c.claim_contramt as decimal(18,2)) 
else cast(c.claim_netamt as decimal(18,2))  end as pih,
case when trim(c.claimno)  like '