Inquiry period

Sir,
As per our State govt Servants Disciplinary and Appeal Rules, the Inquiring Officer has to complete the inquiry within three months from the date of first hearing. But 3 months is about to expire and there is no sign of completing the inquiry for about another 4-5 months. In this situation what can I do. Where should I approach. Should I report to the Disciplinary authority who has appointed the I.O.Pl give me ur valuable advise.