repmgr cannot bring up the standby database after switchover manaully

Hi all,

I have 2 postgresql servers. One is the primary and another one is the
standby. I am trying to setup repmgr to do the switchover manually.
Passwordless ssh have been setup for postgres ID on both servers.

I use this command "repmgr standby switchover --log-level=DEBUG --verbose".
The standy database is able to promote to be the primary. For the previous
primary database, it was shutdown. It was not able to bring up as standby
by repmgr.

Does anyone encounter this issue before? Thanks a lot for any suggestions.

Here is my OS and DB versions:

OS version: CentOS Stream release 8
Postgres DB version: 15.12
rempmgr version: 5.5.0

Here is the repmgr conf files:
>>>>>
node_id=1 # Use 2 on standby
node_name='primary'
conninfo='host=centos804 user=repmgr dbname=repmgr password=xxx
connect_timeout=15'
use_primary_conninfo_password=true
data_directory='/var/lib/pgsql/15/data' # Adjust for your setup
pg_bindir='/usr/pgsql-15/bin'
service_start_command = 'sudo systemctl start postgresql-15'
service_stop_command = 'sudo systemctl stop postgresql-15'
<<<<<

>>>>>
node_id=2 # Use 2 on standby
node_name='standby'
conninfo='host=centos803 user=repmgr dbname=repmgr password=xxx
connect_timeout=15'
use_primary_conninfo_password=true
data_directory='/var/lib/pgsql/15/data' # Adjust for your setup
pg_bindir='/usr/pgsql-15/bin'
service_start_command = 'sudo systemctl start postgresql-15'
service_stop_command = 'sudo systemctl stop postgresql-15'
<<<<<

Regards,
Chris