Why am I getting 402 Payment Required response in my JavaScript app?

We deployed functionality to our network that allows you to disable leave events so you are not billed for those transactions unless you are actually using the Presence add-on. If you do not have Presence enabled, and you want to prevent the 402 responses, you must suppress leave events when you init the PubNub instance.

JavaScript SDK v4

var pubnub = new PubNub({
    subscribeKey: "mySubscribeKey",
    publishKey: "myPublishKey",
    ssl: true,
    suppressLeaveEvents: true // <--- add this
})

JavaScript SDK v3

pubnub = PUBNUB({                          
    publish_key   : 'demo',
    subscribe_key : 'demo',
    ssl: true,
    NOLEAVE: true // <--- add this
})

The 402s should not affect your app negatively but if they do please report your incident to PubNub Support with the details.