You invoke a notification in a customer card page extension, but it pops up in the list page instead? That’s weird. Could you show your code that calls the notification and a screenshot of the result?
Edited: Just tried it myself. Funny thing, but when you call a notification directly in the page trigger, it is shown in the card page, everything is fine. But in case of a page extension notification called in triggers OnAfterGetRecord or OnAfterGetCurrRecord is bound to the list page instead of the card. Other page triggers work as expected. A bug?
I doubt it… The problem is that the webservice is called in the OnAfterGet-trigger and that means that the webservice is run before the page is displayed so it looks like that it gets opened on the list page.
I tried this scenario without any web services - just a dummy notification. Did it in two versions: as a page extension, and direct modification of the page 21. Behaviour is different in these two cases. Besides, it’s still the same if you open the card page and jump back and forth to different customers. Page is displayed for sure, just retrieves a new record on every hop. When notification is called from the extension, it is bound to the list page which is hidden under the card.