Programming Tutorials

  Few things destroy developer velocity like a generic   400 Bad Request   from a financial API. You have authenticated successfully, structured your JSON payload, and initiated the POST request, only to receive an opaque validation error. When integrating with the Payoneer Mass Payouts or Onboarding API, the most common friction point is  strict location data compliance . Sending "USA" instead of "US", or exceeding address line character limits, will immediately trigger rejection errors such as  INVALID_COUNTRY  or  SchemaValidationException . This guide provides a rigorous, frontend-first solution to normalize geographical data and enforce schema validation before your request ever touches the network. The Root Cause: ISO 3166 Standards and Banking Legacy To fix the error, you must understand the constraints of the receiving system. Financial institutions do not parse geographical data loosely; they adhere to strict international standards for Anti-M...