Oracle 23c

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create table your_table (id, message, time, zone) as
select 1, 'A', '1PM', 'PT' from dual union all
select 1, 'B', '1PM', 'PT' from dual union all
select 1, 'C', '1PM', 'PT' from dual union all
select 2, 'D', '2PM', 'FR' from dual union all
select 2, 'E', '2PM', 'FR' from dual union all
select 3, 'F', '3PM', 'TK' from dual
6 rows affected

select id, message, time, zone, count(*) over (partition by id) as cnt
from your_table


ID
MESSAGE
TIME
ZONE
CNT


1
A
1PM
PT
3

1
B
1PM
PT
3

1
C
1PM
PT
3

2
D
2PM
FR
2

2
E
2PM
FR
2

3
F
3PM
TK
1


select id,
  listagg(case when message = 'X' then 'Z' else message end, ',')
    within group (order by message) as messages,
  time,
  zone
from (
  select id, message, time, zone, count(*) over (partition by id) as cnt
  from your_table
)
where cnt < 3
group by id, time, zone
order by id, time, zone;


ID
MESSAGES
TIME
ZONE


2
D,E
2PM
FR

3
F
3PM
TK