No information using a log item

[TalGl]

Hello,

I've a problem using the log option in Zabbix.

for test purposes I'm trying to read the content of the agent's log file using this key:

log["/var/log/zabbix-agent/zabbix_agentd.log"

The agent and the server have no communication problems and perform well with other configured items. The problem is that I don't see any information under Monitoring --> Latest Data --> My defined log item

I didn't find useful information for my problem searching on the net and in this forum. Am I missing something? I'm using a zabbix server ver. 3.0.3 and zabbix agent ver. 2.4, both on Ubuntu 16.04

Best,
Tal