It looks like you are trying to use the AWS Cloud Plugin for Jenkins to connect an EC2 instance with Jenkins installed to the AWS Cloud. It seems that the plugin is unable to obtain the necessary credentials to connect to AWS from the EC2 instance profile.
There are a few potential reasons why this error might be occurring:
The EC2 instance might not have an IAM role associated with it. In order to use the AWS Cloud Plugin, the EC2 instance needs to have an IAM role that allows it to access AWS resources. You can check the IAM roles that are associated with the EC2 instance by going to the EC2 dashboard in the AWS Management Console and selecting the instance.
The EC2 instance might not have the correct permissions to access the metadata service at 'http://169.254.169.254/latest/meta-data/iam/security-credentials/'. This service is used to retrieve the IAM role and credentials associated with the instance. Make sure that the instance has the necessary permissions to access this service.
There might be a problem with the network configuration of the EC2 instance. Make sure that the instance has a valid network interface and that it is able to reach the metadata service.
There might be a problem with the AWS Cloud Plugin itself. Make sure that you are using the latest version of the plugin and that it is configured correctly.