Alguém tropeçou neste mesmo erro:
aws_instance.dev: Creating...
Error: Error launching source instance: Unsupported: The requested configuration is currently not supported. Please check the documentation for supported configurations.
        status code: 400, request id: 3b33649d-6882-43bd-b44c-795a49400252
  on main.tf line 6, in resource "aws_instance" "dev":
   6: resource "aws_instance" "dev" {O script usado foi o seguinte:
provider "aws" {
   version = "~> 2.0"
  region  = "us-east-1"
}
resource "aws_instance" "dev" {
  ami = "ami-0400a1104d5b9caa1"
  instance_type = "t2.micro"
  key_name = "terraform-key"
  tags = {
      Name = "dev"
  }
} 
            