Available schedule slots showing as booked

Explanation

A common reason for this is there's not enough allocated time in the schedule slot. This will be denoted by a "^" symbol in the schedule slot, and means that no public booking can be made here. For example, if your minimum service length is 1 hour, with 15 minutes travel time afterwards, you must have a 1hr 15min  block available on your schedule. Anything less will not be bookable by the public. 

Solution

Increase the length of available time.