FormData not letting me append file in React Js using typescript

I want to send a File in my request using React Js, but I am unable to append file in object of FormData using typescript.
Here’s my React Js Code

    const [imageFile, setImageFile] = React.useState();
      const [productImageMutation, productImageMutationResult]=useAddProductImageMutation();
      const handleUploadClick = (e: any) => {
      var file = e.target.files[0];
      setImageFile(file);
  };
  const handleOnSubmit = (values: Picture) => {
      const formData = new FormData();
      formData.append("formFile", imageFile); //It Gives Error there.
    productImageMutation({ data: formData});
  };

>Solution :

Try to update your state initialization

const [imageFile, setImageFile] = React.useState('');

And also mention a type to you state because in TS you must provide a type