You would have to check your 401(k)'s allowed reasons for distribution, but the purchase of a house isn't generally a "hardship." Getting foreclosed on, that's a hardship. Perhaps you're asking for the wrong category of distribution, or else your plan doesn't allow distributions for the reason that you've got.

Purchase of your primary residence is generally one of the allowable reasons for hardship. The administrator will general ask for the purchase agreement or any other documentation to prove you are purchasing your primary home. These are rarely denied unless you do not provide what they ask for. You may not be aboe to get all of the money, generally you can only withdraw for hardship what you personally have put into the plan - any outstanding loans. The administrator is the only one with all the plan specifics, best to speak with them.

Have you received a denial letter? If the plan administrator asked for documentation on the purchase of the home than you should not be denied for trying to purchase home. We need more specifics if you were denied.