Why can't I see mailing lists created by other users in my organization?

Why can't I see mailing lists created by other users in my organization?

We are looking at moving to Zoho Campaigns, but I can't seem to see any lists or contacts created by the other user in our organization. We use many other Zoho products and most of the staff in our organization have their own usernames. However, Campaigns would not be a suitable product if we are only able to use lists created by our own accounts. Any help would be greatly appreciated!