Gmail error "Unable to attach file"

I am trying to email PDF file using Gmail. However, Gmail app is showing toast:

Unable to attach file

PDF file is not-corrupt and is generated successfully in application's cache directory.

Code: (Please comment below if you need code in Java.):

    val photoURI: Uri = FileProvider.getUriForFile(this, "com.packagename.provider",            File(this.cacheDir.path +"/Report.pdf"))    val emailIntent = Intent(Intent.ACTION_SENDTO)    emailIntent.data = Uri.parse("mailto:")    emailIntent.putExtra(Intent.EXTRA_STREAM, photoURI)    emailIntent.putExtra(Intent.EXTRA_EMAIL, arrayOf("some@domain.com"))    emailIntent.putExtra(Intent.EXTRA_SUBJECT, "subject")    emailIntent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)    emailIntent.addFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION)    startActivity(emailIntent)

Please help