GC- Push subscription creation with Service account - Error

I am trying to create push subscription with push end point, service account and audience using below.

resource “google_pubsub_subscription” “sub”
{
name = “test-sub”
topic = google_pubsub_topic.sample-topic.name

push_config 
{
    push_endpoint = "https://region-${var.project_id}.cloudfunctions.net/xyz/"
	oidc_token 
	{
		service_account_email = "sample-sa@${var.project_number}.iam.gserviceaccount.com"
		audience = "https://region-${var.project_id}.cloudfunctions.net/xyz"
	}
}

}

When I am trying to apply, I am getting below error. Any help to resolve it?

“google api : error 400 : Invalid argument to the service push config::oidc_token::service_account_email”

Thanks