Scope
Some events are not fetched in the frontend Chargebee implementation.
Summary
You might use the Chargebee js to load checkout and self-service in an iframe popup. You may get ALL the events for checkout (in the callbacks), but only get SOME events in the self-service; Example: visit, loaded, close, and payment method, but do not GET events for subscription actions and scheduling actions like subscription changed, subscription canceled, subscriptionResumed, scheduledCancellationRemoved, subscription re-activated, etc.
You get all these events on the webhook or when using the list events API, but not in the frontend Chargebee implementation described below
https://www.chargebee.com/checkout-portal-docs/cbportal-api-ref.html#open
The reason could be due to the domain not being whitelisted in Chargebee
Solution
You need to add their website domain for whitelisting. Then you will receive the other events as well in the portal.