Airbnb false advertising,and I am stranded in a foreign country with no place to live for 10 days

I traveled from South Africa to Dar es Salaam, and I booked accommodation through AirBnb. On arrival at the venue I found another tenant in the room that was listed as vacant. According to the current tenant they also had similar issues. The host deliberately over books the room and then provide an alternative accommodation that had sub-standards to the accommodation that was advertised.