You need to set "Advance booking minimum" to zero for booking creation. Login to MRBS as an admin, go to the "Rooms" page, select the area in question and then click the Edit icon (little pencil). Go to the booking policies section and look for advance booking minimum under "Booking creation". Finally click save.

You can set the default settings for new areas in your config file. See areadefaults.inc.php for more details.

 
👍
1