In Normal view, in the pane that contains the slide thumbnails, click the slide thumbnail that contains the unwanted media.
Note: If your video or animated GIF does not delete, the media has been inserted onto the slide master or associated layout. To delete a video or animated GIF file from a slide master, on the View tab, in the Master Views group, click Slide Master. In Master View, select the slide master or layout that contains the unwanted media.
Select the video or animated GIF.