Getting file from Flask MongoDB but not showing in react app

Question

## This backend code to upload files both image and PDF file Flask==1.1.2 Flask-PyMong0==2.3.0 ##

def file_upload():
    try:
        _json = request.form
        _title = _json['title']
        _desc = _json['desc']
        if 'file' in request.files:
            _file = request.files['file']
            _filename = _file.filename
            _file_mimetype = _file.content_type
            mongo.save_file(_filename, request.files['file'])
        
        user = mongo.db.userReg.find_one({'email': session['user']})
        
        mongo.db.upload.insert_one(
            {'title': _title, 'desc': _desc, 'filename': _filename,
                'file_mimetype': _file_mimetype, 'user': {'userId': user['_id']}, 'date': datetime.datetime.now()})
       mongo.db.upload.find({}).sort('date', -1).limit(1)
       

        message = {
            
            'data': "null",
            'result': {'isError': 'false', 'message': 'File added', 'status': 200, }
        }
        return jsonify(message)
        
    except Exception as e:
      
        return internal_error()

This is viewFile function to get the file response and try to view the file but not showing the image

    import { Document, Page, pdfjs } from 'react-pdf';
    const API = process.env.REACT_APP_API;
    pdfjs.GlobalWorkerOptions.workerSrc =`//cdnjs.cloudflare.com/ajax/libs/pdf.js/${pdfjs.version}/pdf.worker.js`;
    
const viewFile = async (filename) => {
            try {
              const result = await axios.get(`${API}/file/${filename}`, {
                responseType: 'blob'
              }); 
              const fileURL = URL.createObjectURL(result.data)
              setFileURL(fileURL);
              setErrorMsg('');
            } catch (error) {
              if (error.response && error.response.status === 400) {
                setErrorMsg('Error while Viewing file. Try again later');
              }
            }
        };
function onDocumentLoadSuccess({ numPages }) {
    setNumPages(numPages);
    setPageNumber(1);
}
function changePage(offset) {
    setPageNumber(prevPageNumber => prevPageNumber + offset);
  }

  function previousPage() {
    changePage(-1);
  }

  function nextPage() {
    changePage(1);
  }

<div className="files-container">
       {errorMsg && <p className="errorMsg">{errorMsg}</p>}
          {
            (fileExtension === 'pdf') ? (
              <Fragment> 
                  <Document
                       file={fileURL}
                            onLoadSuccess={onDocumentLoadSuccess}
                   >
                     <Page pageNumber={pageNumber} />
                   </Document>
                   <div>
                       <p>
                          Page {pageNumber || (numPages ? 1 : "--")} of {numPages || "--"}
                        </p>
                        <button 
                             type="button" 
                             disabled={pageNumber <= 1} 
                             onClick={previousPage}>
                             Previous
                         </button>
                         <button
                              type="button"
                              disabled={pageNumber >= numPages}
                              onClick={nextPage}
                          >
                            Next
                          </button>
                       </div>
                  </Fragment>
                   ) : (
                   <Fragment>
                       <img src={fileURL} alt={match.params.filename} className="view-file"/>       
                   </Fragment>
                   )
             }         
      </div>       

"react": "^17.0.1", "react-pdf": "^5.1.0". Previously in 2021, I ran the code successfully and showed the both PDF and image file but now this code is not working###

In case of viewing image file, I got only "alt-text" output in view page that not showing any error in console.

In case of viewing PDF file, I got the output "Failed to load PDF file" in view page that showing error in console. "InvalidPDFException"