Item gives always 0 in service monitoring

[SysAdmin_Xomic]

Hello Zabbix Team,
I'm recently configure Zabbix in my office. I added 10 servers as host and monitor their services using Item-Trigger everything is working. But now i add one more host and when i enable the service monitoring it isn't working always show 0 in value when i test the Item.
Item Example:
Item :
Name(HTTP Service)
Type(Zabbix Agent)
Key(net.tcp.service[tcp,,80])

Trigger:
Name(Redis is Down on {host.name})
Expression({Systemctl Services:net.tcp.service[tcp,,80].last()}=0) ### This one is working and notify me when HTTP service is down

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Item :
Name(Mysql Service)
Type(Zabbix Agent)
Key(net.tcp.service[tcp,,3306])

Trigger:
Name(Redis is Down on {host.name})
Expression({Systemctl Services:net.tcp.service[tcp,,3306].last()}=0) ### But this isn't working

Please guide me how to debug this issue.