I have added an image twice by mistake when I was recoding a note. Even though I have deleted the second image from the note, when viewing my images under the "User Media" both appeared and the software does not allow me to delete any of the images.
Try logging into amber.faithlife.com (using your standard Logos credentials) and you should see your media assets there. You can delete them from there.
Thank you Graham, for providing me with this information. I have managed to delete the unwanted images.