Currently, tickets in Help Desk seem to pick a random contact to have as the one that shows up in ticket previews. I can't work out the logic - it's not necessarily the first person who got in contact, as you can add a random contact who hasn't even responded and they will show up in the preview.
It would be really useful to assign a "primary" contact (first person to email) who remains as the visible contact until you manually change it.
Example: Said is the main contact who is responding to the ticket, but Gilda is showing up in the preview as they are an associated contact as well.