How To Fix FMCA_MC_ODATA018 - Form data must use the correct JSON syntax

SAP Error Message - Details

• Message type: E = Error

• Message class: FMCA_MC_ODATA - Message class for the Multichannel oData services(PS)

• Message number: 018

• Message text: Form data must use the correct JSON syntax

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message FMCA_MC_ODATA018 - Form data must use the correct JSON syntax ?

  The SAP error message FMCA_MC_ODATA018 indicates that there is an issue with the JSON syntax in the form data being sent to an OData service. This error typically arises when the JSON payload does not conform to the expected structure or format required by the OData service.
  Causes:
  
  Malformed JSON: The JSON structure may be incorrect, such as missing commas, brackets, or quotes.
  Incorrect Data Types: The data types of the values in the JSON do not match the expected types defined in the OData service.
  Missing Required Fields: The JSON payload may be missing required fields that the OData service expects.
  Extra Fields: The JSON may contain fields that are not recognized by the OData service.
  Encoding Issues: Special characters in the JSON may not be properly encoded.
  
  Solutions:
  
  Validate JSON Syntax: Use a JSON validator tool to check the syntax of your JSON payload. Ensure that it is well-formed.
  Check OData Service Documentation: Review the OData service documentation to understand the expected structure, required fields, and data types.
  Adjust Data Types: Ensure that the values in your JSON payload match the expected data types (e.g., strings, numbers, booleans).
  Include Required Fields: Make sure that all required fields are included in the JSON payload.
  Remove Unrecognized Fields: Eliminate any fields that are not defined in the OData service.
  Escape Special Characters: If your JSON contains special characters, ensure they are properly escaped.
  
  Related Information:
  
  OData Protocol: Familiarize yourself with the OData protocol and its conventions for data representation.
  SAP Gateway: If you are using SAP Gateway, check the service implementation and the data model to ensure compliance with the expected JSON structure.
  Debugging Tools: Use tools like Postman or Fiddler to test your OData requests and inspect the JSON payload being sent.
  Error Logs: Check the SAP application logs for more detailed error messages that may provide additional context about the issue.
  
  By addressing the above points, you should be able to resolve the FMCA_MC_ODATA018 error and successfully send the correct JSON syntax to the OData service.