You load a new publisher account into the application but you cannot see it in the Channels tab. Maybe you cannot see your Campaign names in the Campaign tab. For example, you might be trying to change the publisher account name.
To see your publisher account names in the grid from the Channels tab, click the View Builder link in the upper-right of the grid.
Remove all metrics columns and save your changes. You should now see your missing Publisher Accounts in the Channels tab screen. You can now re-add your metrics columns through the View Builder.