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Go to the site the publisher has been added to.
In the top right corner select the cog icon to open the “Settings” menu. Note: it may take a few seconds for the cog to appear when first loading the page.
Select Site contents
Select Content Approval Matrix from the list of items
Select the department the publisher is assigned to, select the three dots next to the department name, then select edit. Note: only select one department at a time, trying to configure multiple departments at once will overwrite any existing approvers.
In the Approvers box, search for and select the publisher you want to add, and/or select the X next to a given name to remove an approver. When you are done making changes select Save at the bottom: