You can go directly to the room you forgot to open with your membership card, and leave your room card in the room and go directly. Will something happen, such as any responsibility or hotel?

In my experience, you are a little dangerous, especially if you are gambling on credit cards, which will be more troublesome. Because you didn't inform the hotel to check out, and you didn't go through the procedures of ward round and check out, according to the normal process, the hotel will default to your continued renting. Unless the hotel room is busy and business is good, you will check out directly according to your scheduled time.

However, according to the default renewal process, the hotel still needs to call you to the front desk to handle the card pressing procedure again (that is, pay the deposit) in order to complete the renewal process. If you don't get a call, just pay attention to the recent consumption record of the credit card. If there is extra rent or other consumption expenses, you can still get them back by booking the original order time, and the hotel has not informed the renewal fee or signed it for confirmation.

If you pay cash (just rent), you don't have to worry. Basically, it won't happen that you save for many days and then ask others for money.

But I still hope to pay attention to the checkout process next time and be a responsible tourist. After all, it is convenient for other tourists to feel at ease. Now we advocate civilized travel. I hope you have a pleasant trip.