why pre - approve request cost different from what I set at the web?

[Kevin191]

Here is my listing https://www.airbnb.com/rooms/8130578?checkin=01%2F06%2F2017&checkout=01%2F09%2F2017&guests=1&adults=...

Guest sends a request for two days from Jan 8 till Jan 10 with total price  832$, then I thought that it is strange since it is 399$ per night plus cleaning fee and all taxes. When I check online the same dates it gives me 1090$. What do I suppossed to do?