The respondent shall, within the time specified in the order or any extension thereof as the commission grants, file its answer with proof of service on the complainant and the consumer advocate. All grounds of defense, both of law and of fact, shall be raised in the answer. If the respondent has no information or belief upon the subject sufficient to enable an answer to the allegation, it may so state in the answer and place its denial upon that ground.
Haw. Code R. § 6-83-101