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Perform following to update DocumentDB master user namedeletion protection:
Login to the AWS Management Console at https://console.aws.amazon.com.
Navigate to DocumentDB console.
In the Navigation pane, choose Databases.
Click on the Database Cluster to be modified, click Modify.
Under Deletion Protection, select enable deletion protection checkbox.
Click on the Continue button
Under Scheduling of modifications option select Apply Immediately.
Click on Modify Cluster button..
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