@Emily1785 I am sorry that the County is requesting back taxes.
Unfortunately, it is not the responsibility of AirBnB or any management company for that matter to inform you about the taxes that are charged for STRs. It is the responsibility of the host to know this information, and most local tax departments will have someone who can explain the local tax situation.
@Good-Reviews-Only0 If AirBnB does not have an agreement to collect taxes, it is up to the individual host to set up the taxes for their listing. You have noted that there are hosts who do not appear to be collecting TOT in your area. Just because it is not listed as a tax on the booking page does not mean that the host is not collecting the required taxes. It just means that they are not being transparent about it.