Steps to reproduce:

1. Installed Zabbix Agent 6.0.21 on Ubuntu 18.04 and configured client and PostgreSQL 11.20
2. Add template to the host into Zabbix server
3. Followed 100% instruction on Zabbix website

Result:
Data are collected and visible on Zabbix server, however Postgresql server shows on log:

2023-09-07 19:51:03.192 UTC [11251] zabbix@zabbix FATAL:  role "zabbix" does not exist
2023-09-07 19:52:03.146 UTC [11408] zabbix@zabbix FATAL:  role "zabbix" does not exist
2023-09-07 19:53:03.114 UTC [11564] zabbix@zabbix FATAL:  role "zabbix" does not exist
2023-09-07 19:54:03.248 UTC [11720] zabbix@zabbix FATAL:  role "zabbix" does not exist
.....

Expected:

There should not be any error because the user is zbx_monitor and not zabbix.

PostgreSQL 11.20 (Ubuntu 11.20-1.pgdg18.04+1) on x86_64-pc-linux-gnu, compiled by gcc (Ubuntu 7.5.0-3ubuntu1~18.04) 7.5.0, 64-bit)