Improving Client Follow-Up Workflow to Avoid Ghosting

Is there a better way to structure this? Scenario: A customer misses a scheduled consultation call. Lindy follows them up via email to rebook a call. Issue: Lindy sends the first email but when the client replies Lindy does nothing. The Task run says Conditions are not met so she continues to 'Observe' the task. Question: What is stopping Lindy from continuing to converse with the client? And is there a better way to structure the workflow so she does not 'ghost' them?