To activate alerts for account transactions with American Express Serve, users can typically access the Serve account online or through the mobile app. Once logged in, it is important to look for the section related to account settings or notifications. Here, users will usually find options to customize alerts for transactions, such as text messages or email notifications. Users can select their preferred types of alerts, including notifications for purchases, deposits, or balance updates. It is advisable to ensure that the contact information provided, such as the mobile number or email address, is accurate to receive these alerts promptly. For further details or potential changes to the alert options, users may want to visit the relevant sections on the official American Express Serve website, where they can find the most current information.