Restoration will reduce the length of clumsy, stupefied, and enfeebled (and drained at higher ranks). Dispel magic will remove magical effects, and neutralise poison/remove disease/curse, and restore senses as their names imply. That covers most conditions.

Resting will reduce some conditions as well, like drained. You could play it that a rest also reduces things like clumsy/stupefied/enfeebled.

It could also be that this specific haunt is just missing a duration or other text indicating how to remove the condition.

Ultimately it’s up to the GM to adjudicate this if they feel like something is amiss or unfairly punishing.