Hello Stuti,
Currently t3a.medium instances are not supported by the Wazuh All-In-One Deployment AMI.
If I try to use a t3a.medium instance (or many others) I get this error
"The instance configuration for this AWS Marketplace product is not supported. Please see the AWS Marketplace site for more information about supported instance types, regions, and operating systems."
This means that the instance size is being restricted in the AMI by Wazuh.
The pricing problem is not AWS, it is Wazuh forcing us to use a more expensive instance when it is not necessary.