Need help on PIVOT table

[zxmgh]

Hi, I have a table I need to pivot the result:

create table tab1 (col1 varchar2(50), col2 varchar2(50), col3 varchar2(50));

insert into tab1 (col1, col2, col3) values ('pk1', 'type1', 'pk1_type1_value1');
insert into tab1 (col1, col2, col3) values ('pk1', 'type1', 'pk1_type1_value2');
insert into tab1 (col1, col2, col3) values ('pk2', 'type1', 'pk2_type1_value1');
insert into tab1 (col1, col2, col3) values ('pk2', 'type2', 'pk2_type2_value1');
insert into tab1 (col1, col2, col3) values ('pk2', 'type2', 'pk2_type2_value2');
commit;

-- I need the output like the following, comma dilimited values for type1_value and type2_value:

col1     type1   type1_value                                         type2   type2_value
pk1      type1   pk1_type1_value1,pk1_type1_value1    null      null
pk2      type1   pk2_type1_value1                               type2    pk2_type2_value1,pk2_type2_value2

-- my select
select tab1.col1, case when tab1.col2 = 'type1' then 'type1' else null end  as type1,
                  listagg((case when tab1.col2 = 'type1' then tab1.col3 else null end), ',') within group (order by tab1.col3) as type1_value,
                  case when tab1.col2 = 'type2' then 'type2' else null end  as type2,
                  listagg((case when tab1.col2 = 'type2' then tab1.col3 else null end), ',') within group (order by tab1.col3) as type2_value
                  
from tab1
group by tab1.col1, case when tab1.col2 = 'type1' then 'type1' else null end, case when tab1.col2 = 'type2' then 'type2' else null end;

-- the output shows two rows for pk2, how to combine the two rows into 1
col1    type1   type1_value                                      type2  type2_value
pk1    type1   pk1_type1_value1,pk1_type1_value2  null     null
pk2    null      null                                                   type2  pk2_type2_value1,pk2_type2_value2
pk2    type1   pk2_type1_value1		       null   null