Date picker allows to pick already booked time

Support forumCategory: BugsDate picker allows to pick already booked time
Artur asked 2 years ago
After making an appointment and confirming it, calendar still allows to pick time which stands as booked in admin panel.
In addition to that, calendar shows wrong available hors which don't match appointment settings (booking more time than expected, despite not having block time set).

Console shows errors with mismatched jQuery version
Bootstrap's JavaScript requires jQuery version 1.9.1 or higher, but lower than version 3