Photomerge not working

Hi, I'm using the newest update of Photoshop CC, 2018 19.0 release and every time I try to photomerge two poor more pictures together it closes out right before it's done and brings me back to the main "home screen", if you will, of Photoshop with all the recent opened images showing on the dark grey background. Can anyone help me with this? I've tried restarting Photoshop and the computer and I've also tried it on a different computer and still had the same problem...any suggestions would be appreciated, thanks!