We are host, we received a group client. During check in, they checked everything and signed check list paper. On the 4th day, they began to message us our dish washer had a big flood. When we replied them we will go to check and repair, they messaged us they already repaired and cleaned all water in a very short time. When we arrived there, they were not there, house locked. We waited until evening, then we found nothing about water, machine works well. We asked them what about others? Everything all fine? Ok for them? They said ok. The day after we received airbnb information that they asked price reduction or compensation for water problem. We rejected and did not receive any contact until they check out. Then after they checked out, they gave us a very bad comment, listed a lot of problem we never heard and never true, we also received their request to ask a big amount compensation. After we submitted all prove document to show the airbnb what was real situation. Airbnb replied to us that they need to balance clients and host, so they defined an amount of money to compensate to this client. For us, this is a very obviously hook and crook money behavior. How could we protect us? Is there any process to ask airbnb to do more investigation? is there any black list for this kind of client to avoid them to hurt other hosts?