You cannot update Veeam Backup for AWS operating in the Paid edition to version 2.0 from the Veeam Backup for AWS Web UI. To update the product, you must install Veeam Backup for AWS version 2.0 from AWS Marketplace on a new EC2 instance, and then migrate Veeam Backup for AWS data to the new EC2 instance. For information on how to perform the migration procedure, see this
Veeam KB article.