I suggest you do a little legal research and/or consult with a landlord-tenant attorney immediately.
If the tenant is in possession of the property, they clearly have not been evicted and this makes me wonder if you know what an eviction is.
Unless your tenant has agreed to leave, or you have legal authority to have the police remove them, putitng pressure on them to leave could very well bring you additional civil or even criminal liability.
Any lease or rental agreement provisions you have with your tenant are a matter of a private, civil contract between you and your tenant, and likely, none of Airbnb's business and certainly not something Airbnb is likely to act on or enforce.
I am sorry for any negative situation you may be in, given California's extreme tenant protections, but I do not think this is likely the forum to help, nor that Airbnb is likely to have any reason to take action here.
One more time, I strongly encourage you to educate yourself on tenants' legal rights and responsibilities in your jurisdiction, and to remain within the law. Hopefully if you don't want them, you can find some resolution to get the to move out without great expense to you-- which may include the necessity of payment to them, if less than attorney's fees.
Finally, Nolo Press up in Berkeley, has a number of books on these matters; you could file an eviction proceeding yourself, if you're well-prepared and actually (legally) in the right, but again, tenant protections are extreme in California and it might take six months in the best of circumstances.
Good luck.