Strange MySQL behavior : Access denied for user '3306'@'localhost'

[t.heroult]

Info
Zabbix server 5.4 (Debian 10)
host :
- windows 2016 std
- MySQL 5.7
- Zabbix agent 2
- Template : MySql by Zabbix agent

Hi folks !
I'm rather new to zabbix. I discovered it few weeks ago and I'm currently setting it in our information service...

[tazzzabbix]

Hi All

I'm really hoping someone can help me with this as I have no idea. I must warn you I know nothing about mysql
Would someone be able to send me the mysql code that I must use to get the same details as the "availability report" on Zabbix.
What I'm trying...