Esp32 error 400 upload spiffs wav file to web server using http post

Projects Networking, Protocols, and Devices
6

hi kenB thanks for the response, the curl command works fine, i have a esp32-s3-n16r8, the psram is enabled on the arduino IDE, i flipped the boundary string as you suggest.
im a relative newbie using esp32, could you enlighten me about to do a more efficient multipart stream.
i tried to send the audio file directly as follow but get the same http 400 error

HTTPClient client;
  client.begin("http://192.168.1.112:5000/upload");
  client.addHeader("Content-Type", "audio/wav");
  int httpResponseCode = client.sendRequest("POST", &file, file.size());
  Serial.print("httpResponseCode : ");
  Serial.println(httpResponseCode);