curl --request POST \
  --url https://api.example.com/v1/Accounts/{account_sid}/VoipCarriers \
  --header 'Content-Type: application/json' \
  --data '
{
  "application_sid": null,
  "diversion": null,
  "e164_leading_plus": 1,
  "is_active": 1,
  "name": "my carrier",
  "register_password": null,
  "register_sip_realm": null,
  "register_username": null,
  "requires_register": 0,
  "tech_prefix": null
}
'

{
  "sid": "3eff2e0b-9870-4cc0-aa96-363e703c37ab"
}