How to send a multipartFile to an api using react and spring - reactjs

Question

Hi I am trying to connect a react-app with an api that i did with react. The problem is that I can not send a multipartFile to the api side. If I do the request with postman, work correctly. But if i do the request in my react-app do not work.
#Spring
Spring code
#PostMapping("/save")
public ResponseEntity<?> save(#RequestParam(required = false) String folderId, #RequestParam MultipartFile multipartFile) throws IOException{
//folder exist??
int id = Integer.parseInt(folderId);
Optional<Folder> folderOpt = folderService.get(id);
if(folderOpt.isEmpty()){
return new ResponseEntity<>("The folder does not exist", HttpStatus.NOT_FOUND);
}
Folder folder = folderOpt.get();
//connect with cloudinary
BufferedImage bi = ImageIO.read(multipartFile.getInputStream());
if (bi == null){ //is it an image??
return new ResponseEntity("Image does not valid", HttpStatus.BAD_REQUEST);
}
Map result = cloudinaryService.upload(multipartFile);
//save in the bd
Image img = new Image(
(String)result.get("original_filename"),
(String)result.get("url"),
(String)result.get("public_id"));
img.setFolder(folder);
imageService.save(img);
return new ResponseEntity<>(HttpStatus.OK);
}
#Postman
Postman request
#React
React code
const [imageSelected,setImageSelected] = useState("")
const uploadImage = (files) =>{
const formData = new FormData();
formData.append("file", files[0]);
console.log(formData)
ImagenServices.postImage(formData,id)
}
return(
<div className={Styles.container}>
<div>
<input type="file" id="myFileField" onChange={(event) => {setImageSelected(event.target.files)}}/>
<button onClick={() => uploadImage(imageSelected)}>Upload image</button>
</div>
</div>
)
#PostImage service
Service code
async postImage(file,idFolder){
let request = await fetch(REST_API_URL + "/save",{
method: "POST",
body:{
'folderId': idFolder,
'multipartFile': file
},
headers:{
'Accept': 'application/json, text/plain, */*',
'Content-Type': false
}},
)
}
}
#Error
console error
ERROR 95787 --- [io-8080-exec-10] o.a.c.c.C.[.[.[/].[dispatcherServlet] : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is org.springframework.web.multipart.MultipartException: Current request is not a multipart request] with root cause
org.springframework.web.multipart.MultipartException: Current request is not a multipart request
at org.springframework.web.method.annotation.RequestParamMethodArgumentResolver.handleMissingValueInternal(RequestParamMethodArgumentResolver.java:210) ~[spring-web-5.3.22.jar:5.3.22]