Hanoi Fiesta Central Hotel and Spa

Black mold and bugs, refused to refund. We booked 2 rooms and were given 403 and 503. There was water on the floor and small water bugs in the restroom of 403, so I did not spend the night there. I showed the receptionist and they didn't have any other rooms available, so I stayed in 503 with my mom the first night, hoping to get another room the next day. We realized that 503 had water damage all along the wall connected to the tub, so water likely leaked down to 403 which was directly below it. Both rooms were very damp and the sheets felt sticky. We checked out the next day and offered to pay for that night in 503. The manager wasn't present at check-in or at check-out the next day so we were told to request a refund through hotels.com. I requested a refund, and then did not receive a follow-up a week after I had been promised one. I checked in again, and Hotels.com tried the manager again, and the manager did not approve the refund. Even if there was a cancellation policy, how would I know that the room would have mold?