Hello Everyone, I have a problem with a particular item

I'm currently trying to create an item that gets me the serial number of a Host, to inject it in the inventory part of zabbix, I have tested my key to see if it allows me to retrieve the serial number of my host, it is the case 

Once I checked my item's key, I thought it was enough to switch my host's inventory to "automatic" mode:

my item is "Zabbix Agent (Active)" type, I thought I would just have to wait 60sec, because :

However, after more than 30 minutes of waiting, after restarting the agent service and after waiting again for more than 30 minutes, my host still does not have the value that appears in the "Inventory" tab: 

whereas if I set my sample item to "Zabbix Agent" and test the item from the server on my host's IP:

I don't understand why the information doesn't come up automatically like all the other items that have the item type Zabbix Agent (Active):