Arrived at our accommodation around 8pm after a long day of travelling just to find a man sneaking around in the dark in our room, thinking we had the wrong room we apologised for intruding and shut the door. Contacted the host to confirm our room number was correct which it was then continued to inform the host of the situation and asked why there was someone already in our room. Their advice was far from helpful - saying it could be a maintenance man or the cleaner. Maintenance at 8pm? Cleaning in the dark? They asked we go back and check which I refused - worried for our safety. Only upon further investigation did they inform us that the previous guests had reported a stolen key. Unacceptable to not let us know ahead of our arrival and to not change the locks. They offered another room however it only had one bed and there was three of us. We wasted almost two hours late at night feeling unsafe trying to find a solution before I finally refused to stay somewhere some random guy had key access too so I returned our key, demanded a full refund and got Airbnb support involved who on the other hand were absolutely excellent, easily contactable and responded immediately despite it being late at night they had heard my situation and processed my full refund within 10 minutes of my call.