Click OK in each dialog and save the document.
Note that you will still need to accept or reject all the changes this is just for viewing, you still need to accept or reject all of the changes before your document is complete. Another community question Comments in Word 2016 displayed as 'Author' says the answer is 'To make reviewer names stay for future comments, go to File > Options > Trust Center > Trust Center Settings > Privacy Options and clear the check box for 'Remove personal information from file properties on save'.
You can reject all changes at once by clicking on the pulldown below the Reject icon and selecting Reject All Changes in Document. To reject a change, click on the changed text, and then click the Reject icon in the Changes Group of the Review Ribbon.You can accept all changes at once by clicking on the pulldown below the Accept icon and selecting Accept All Changes in Document. To accept a change, click on the changed text (or use the arrow to get to the change), and then click the Accept icon in the Changes Group of the Review Ribbon.Use the Next and Previous icons in the Changes Group of the Review Ribbon to move back and forth to the various changes. Normally, you will reject all comments – after you address the issue! Once you have all of the documents combined into one, you need to accept or reject all of the changes and comments.