EC2 metrics are not showing in inventory while creating Alerts

Hi,

I was trying to create alerts for EC2 CPU usage. The metrics for aws.ec2.cpu.total.pct is appearing fine in Kibana.

However, when I am trying to create an alert for the following condition and run a preview

Inventory

Conditions

FOR EC2 Instances

WHEN CPU usage

IS ABOVE 90

%

FOR THE LAST 1 minute

I am getting the following message

There were 0 instances across 3 awsEC2s that satisfied the conditions of this alert in the last hour.

I have around 12 EC2 instances. why its showing on 3awsEC2s.

Regards,
Minu