curl --request POST \
  --url https://api.avenia.io:8443/v2/v2/kyc/w8ben \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "useDigitalSignature": true,
  "foreignTinNotLegallyRequired": true,
  "isClaimingTaxTreatyBenefits": true,
  "treatyArticle": "<string>",
  "treatyIncomeType": "<string>",
  "treatyWithholdingRate": "<string>",
  "treatyExplanation": "<string>",
  "usTin": "<string>",
  "referenceNumber": "<string>",
  "mailingAddress": {
    "streetAddress": "<string>",
    "city": "<string>",
    "state": "<string>",
    "zipCode": "<string>",
    "country": "<string>"
  }
}
'

{
  "id": "<string>",
  "w8BenUrl": "<string>"
}