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.

According to the rules on conditions, they last until the duration ends, until they are removed, or the terms dictated in the condition to end it are fulfilled.

https://2e.aonprd.com/Rules.aspx?ID=774

The one exception I’m aware of is persistent damage, which generally ends after 1 minute if you are unable to succeed your DC15 flat check.