ssekmsKeyId

If you specify x-amz-server-side-encryption with aws:kms, you must specify the x-amz-server-side-encryption-aws-kms-key-id header with the ID (Key ID or Key ARN) of the KMS symmetric encryption customer managed key to use. Otherwise, you get an HTTP 400 Bad Request error. Only use the key ID or key ARN. The key alias format of the KMS key isn't supported. Also, if the KMS key doesn't exist in the same account that't issuing the command, you must use the full Key ARN not the Key ID.

Your SSE-KMS configuration can only support 1 customer managed key per directory bucket's lifetime. The Amazon Web Services managed key (aws/s3) isn't supported.