Why in pro version chips are not working correctly?

// MY JQUERY code sample as follows: 
$('.chips').on('chip.add', function(e, chip){
      console.log(chip.tag); // works
});

$('.chips').on('chip.delete', function(e, chip){
      console.log(chip.tag); // works 
});

$('.chips').on('chip.select', function(e, chip){
     console.log(chip.tag); 
     // NOT WORKING THOUGH WHEN CHIP SELECTED ATTRIBUTE SELECTED IS ADDED 
}); 

$('.chips-placeholder').materialChip({
    placeholder: 'ENTER A TAG',
    secondaryPlaceholder: '+TAGS',
});


// MY HTML CODE is as follows:
<div class="chips chips-placeholder"></div>

I've paid for pro version why it's NOT working properly?