Fix bug when an admin user makes a booking and bookings are forced to…

… be private. See GitHub Issue #3770.

web/edit_entry_handler.php

@@ -375,15 +375,19 @@ function invalid_booking(string $message) : void
   $month_relative = $month_relative_ord . $month_relative_day;
 }
 
-// Handle private booking
-// Enforce config file settings if needed
-if ($private_mandatory && !is_book_admin())
+// Handle private bookings.
+// If the area settings allow users to make private bookings then use the value from
+// the form, unless the privacy status is forced and the user is not an admin (admins
+// are allowed to make public bookings if they want, even if the status is forced).
+// Otherwise the booking is not private, unless the status is forced, in which case
+// the default applies, whether or not the user is an admin.
+if ($private_enabled)
 {
-  $isprivate = $private_default;
+  $isprivate = (!is_book_admin() && $private_mandatory) ? $private_default : (bool) $private;
 }
 else
 {
-  $isprivate = (bool) $private;
+  $isprivate = ($private_mandatory) ? $private_default : false;
 }
 
 // Make sure the area corresponds to the room that is being booked