Hello @RobertF208 ,
All your contacts' details that match the column criteria are shown in the segment. I'd advise checking what columns you currently have setup to show for your segments. If First Name and/or Last Name aren't one of the columns you have up, then you won't be seeing your contacts' names on your end when doing so. Otherwise, I'd suggest calling in like chat support suggested last month, so our phone agents can screenshare with you and continue troubleshooting live.