curl --request PUT \
  --url https://api.tenbytecloud.com/v1/network/load_balancers/{load_balancer_uuid}/billing_account \
  --header 'Content-Type: application/json' \
  --header 'apikey: <api-key>' \
  --data '
{
  "set_id": 123456
}
'

{
  "uuid": "438ac62f-e97b-4ef0-8940-507b9e94af43",
  "display_name": "my new LB Name",
  "billing_account_id": 123456
}