The PostgreSQL database cannot start after modifying the IP
When restarting the server with a specific logfile (see your restart command: /usr/pgsql-12/bin/pg_ctl -D /postgres -l logfile start) you need to look at that specific logfile, not at postgresql-Sat.log.
Moreover, this line in the previous log shows that you modified the data directory:

2020-07-04 09:23:14.943 EDT [1832] LOG:  parameter &quot;data_directory&quot; cannot be changed without restarting the server


Presumably log_directory is relative to the data directory, so after this change you need to look at the new location now to find the new logs.
From the documentation:

log_directory (string)
When logging_collector is enabled, this parameter determines the directory in which log files will be created. It can be specified as
an absolute path, or relative to the cluster data directory. This
parameter can only be set in the postgresql.conf file or on the server
command line. The default is log.