Special Characters of MultipartFile file is converted into ? in springboot

Question

when I upload a file and pass it to Rest Controller the special chars of filename are converted into ? in spring boot .for example ```.pdf is converted into ???.pdf.

before rest call:

for (FileMessageResurce file : files){
    MultiValueMap<String, Object> request = new LinkedMultiValueMap<>();
    request.add("file", file);
    // ...
    call to controller

controller class:

    ResponseEntity<SuccessResponse<Tuple>> upload(
    @RequestPart("file") MultipartFile file)