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No log for adding email to a customer
By default, for every activity performed on the Chargebee site, there will be an activity log created. If the email details are given during customer creation then the event when the email got added is not logged separately. It just shows as a 'Customer created' event.
There are two instances where the email address of the customer gets recorded in Chargebee.
The detailed view will have the email address
You can find the 'Activity log' section at the bottom of the Customer section and it applies to every other setting as well.
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