A+ Sorting Appointment Date Defect?

Hello -
I noticed when sorting data on the All Appointments shortcode, the date sorting is not working as would be expected.

When sorting by dates earliest to latest, I would expect Jan 8th appointments to be displayed before Jan 9th but in the application the order being displayed it:
Jan 9
Jan 8
Jan 19
Jan 17
Jan 12

This needs to be fixed urgently. Can you please tell me how to fix it.

Thanks
Vandana