Step 1- Go to your module and click the page under the materials section for which you want to change the writer.
Step 2- When the pages opens, click Edit at the top right of the page.
Step 3- Click the dropdown to see the list of writers and select the writer you want.
Step 4- Click Save at the top right of the page.
That's it 😊!
Please find below a walkthrough of the above steps-