Issue:
When adding a new newsletter to Magento via custom module,
Observer NewsletterSubscribeObserver not called, but after saving newsletter to the Magento calls another Observer UserProfileNewsletterSubscribeObserver and try to get a customer by ID, Magento throws Exception because a customer with ID=0 doesn't exist.
As a result, an event about a new newsletter doesn't send to Klaviyo.
Issue: When adding a new newsletter to Magento via custom module, Observer NewsletterSubscribeObserver not called, but after saving newsletter to the Magento calls another Observer UserProfileNewsletterSubscribeObserver and try to get a customer by ID, Magento throws Exception because a customer with ID=0 doesn't exist. As a result, an event about a new newsletter doesn't send to Klaviyo.
Related issue: #19
Steps to reproduce:
Expected result: Email what was subscribed should get "Welcome email"
Actual result: "Welcome email" doesn't send