update with sub query successful but not updating - sql-update

Question

We have wrong duplicate id loaded in the table and we need to correct it.
The rules to update the id is whenever there is a time difference of more than 30 min, the id should be new/unique.
I have written the query to filter that out, however update is not happening
The below query is there to find the ids to be updated.
For testing I have used a particular id.
select id,
BEFORE_TIME,
TIMESTAMP,
datediff(minute,BEFORE_TIME,TIMESTAMP) time_diff,
row_number() over (PARTITION BY id ORDER BY TIMESTAMP) rowno,
concat(id,to_varchar(rowno)) newid from
(SELECT id,
TIMESTAMP,
LAG(TIMESTAMP_EST) OVER (PARTITION BY visit_id ORDER BY TIMESTAMP) as BEFORE_TIME
FROM table_name t
where id = 'XX1X2375'
order by TIMESTAMP_EST)
where BEFORE_TIME is not NULL and time_diff > 30
order by time_diff desc
;
And i could see the 12 record with same id and time difference more than 30.
However when I am trying to update. the query is succesfull but nothing is getting update.
update table_name t
set t.id = c.newid
from
(select id ,
BEFORE_TIME,
TIMESTAMP,
datediff(minute,BEFORE_TIME,TIMESTAMP) time_diff,
row_number() over (PARTITION BY id ORDER BY TIMESTAMP) rowno,
concat(id,to_varchar(rowno)) newid from
(SELECT id,
TIMESTAMP,
LAG(TIMESTAMP) OVER (PARTITION BY visit_id ORDER BY TIMESTAMP) as BEFORE_TIME
FROM table_name t
where id = 'XX1X2375'
order by TIMESTAMP_EST)
where BEFORE_TIME is not NULL and time_diff > 30
order by time_diff desc) c
where t.id = c.id
and t.timestamp = c.BEFORE_TIME
;