Dear Experts

I have these codes

text TO cmd TEXTMERGE noshow

select distinct(vou_no)as vou_no,MAX(date)as date,MAX(acc_code)as acc_code,
(case type1 when 'P' then SUM(cr_amount) end )as A_amount,
(case type1 when 'A' then SUM(cr_amount) end )as A_amount,
(case type1 when 'D' then SUM(dr_amount) end )as D_amount
 from crsalp where date=?thisform.text4.value
 group by vou_no
 
 ENDTEXT

type1 is a field (char 1)

This query show following error message

Column 'crsalp.type1' is invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause.

I want to get SUM(cr_amount) in case type1=P,A,D

Please help