Zod validation considering a File object to be a String (C:\fakepath\file.jpg) when submitting a form with react-hook-form

I'm building a NextJS15 Form with useForm() hook and Zod validation that includes a file Input. Unfortunately, when I try to submit the form, Zod considers the uploaded file as a String (C:\FakePath\File.jpg) instead of considering a File object.

Zod Error

As long as the form is not submitted, I checked that form.getValues('media') is an instance of File, and it is.

But when I hit the submit button, Zod throws an error saying that 'media' is not an instance of File.

See the bits of code below :

const formSchema = z.object({
    ...,
    media: z.instanceof(File).optional().nullable(),
    ...,
})

export default function QuizForm() {
    const handleImageUpload = (event, index) => {
        const file = event.target.files[0]
        if (file) {
          form.setValue(`questions.${index}.media`, file);
        }
    }

    const form = useForm({
        resolver: zodResolver(formSchema),
        defaultValues: {
            ...,
            media: null,
            ...,
        }
    })

    async function onSubmit() {
        const formData = form.getValues()
        
        formData.questions.map((question, index) => {
            console.log(question.media) // This outputs C:\\FakePath\\File.jpg
        })
    }

    // File Input Component
    <Input
        type="file"
        accept="image/*"
        onChange={(e) => {
            handleImageUpload(e, index);
            field.onChange(e);
        }}
    />
}

I'd like some explanation on this and maybe a solution because AI prompting didn't get me out of this issue ;)

Thanks !