Remove detachable hooks and other hardware when the curtain's care instructions require it. Small hard fittings can snag fabric, make noise or become loose during movement.
Understanding this situation
Check the curtain label as well as any lining, weights or decorative trim. Large curtains can exceed a programme's practical capacity before they look heavy, and not every curtain material is machine washable.
A useful next step
Prepare the curtain outside the machine and use an appropriate permitted programme. If a hook is missing after washing, do not search inside concealed machine spaces. Report any accompanying scraping or snagging and avoid further operation until the risk is understood.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.