Curious that the Delivery Advisor said it wasn't available; did you ask why? Should be an available feature. Depends on having the cameras and sensors working, of course, and a few other things. Have you reviewed "Parking Experience" in the Owner's Manual for the procedure? I assume you're trying this in a parking lot, you stop, press the P/A symbol on the Pilot Panel, and then drive slowly past some parking spaces as it searches for good spots. Based on what you're saying, either the P/A symbol doesn't display or "Not Available" pops up when you do.
A conversation with Customer Service may be in order.