That Listening Mode is a relatively recent change and may not function as expected. We’ll check internally how we can improve it.
However, you don’t actually need the Listening Mode to test your triggers. In the Lansweeper trigger, if you clicked on “Instance Deploy,” and then manually created a new asset, the event should appear under the Test tab (Run panel at the bottom). In the next step, add a "Get asset details" action and reference the asset key in the trigger event. That asset key is available at results.body.data.events. You should loop over that path, as a single trigger run can include multiple events.
For a working example of looping over trigger events, you can also check the “Apple Device Stock Transition” template.

