When the file upload does not open on the page deployed with flutter web

InputElement uploadInput = FileUploadInputElement();    
void uploadFileFlume(String imageType){
      uploadInput.draggable = true;
      uploadInput.accept = '.png,.jpg,.jpeg,.svg';
      uploadInput.click();
      uploadInput.onChange.listen((e) {
        final files = uploadInput.files;
    
        print(uploadInput.files.first.name);
        List<String> fileType = uploadInput.files.first.name.split('.');
        String type= fileType[1]; 
        print(type);
        final reader = new FileReader();
    
        if (files.length == 1) {
          final file = files[0];
    
          reader.onLoad.listen((e) {
            sendFile(reader.result, type, imageType);
          });
    
          reader.readAsDataUrl(file);
        }
      });
    }

The code to select a file is as above. Locally, file selection became smooth, but after deployment, the window to select a picture does not appear. What's the problem? plz help me