API Gateway "Unsupported Media Type" Error when sending application/x-www-form-urlencoded data

Hello Team

I am creating a REST API that accepts data with Content-Type of application/x-www-form-urlencoded. I test the api in aws but receive 415 error, Unsupported Media Type.

I have tried setting up the API based on the questions and answers here and here but have not been able to resolve the error. The settings are shown below. Please help me with this.

Thanks.

API Result

• Headers
  • Content-Type:application/x-www-form-urlencoded
• Request Body
  • a=1

Method Request

• All default settings.

Integration Request

• Request body passthrough
  • When there are no templates defined (recommended)
• Mapping Template
  • application/x-www-form-urlencoded

Integration Response

• Mapping Template
  • application/json
  • application/x-www-form-urlencoded
    • Both specify the same Json template.

Method Response

• All default settings.

Settings

• Binary Media Types
  • application/x-www-form-urlencoded