A non-serializable value was detected in an action (redux-toolkit)

In the payload of the action in the store, I store the downloaded file with the File type, which will then pass verification in the saga

  const form = new FormData();
 
   if (privateKey && privateKey instanceof Blob) {
     const blob = new Blob([privateKey], { type: 'multipart/form-data' });
     form.append('privateKey', blob);   

and then send to backend

every time after downloading a file there is an error in the console

How can I fix it?
disabling the serializable-check – for me it’s not good idea