Kiip web sdk integration showing bad request error in console

I just integrated KIIP SDK for web in my node js application and it works correctly . But the problem is it showing error on browser console on each page refresh, But this error does not affect working of this sdk, it works perfectly.

the errror message showing is,

'POST http://ift.tt/1ad1XTE 400 (Bad Request)'.

My kiip code integration is as follows,

1) Included the script file on head tag

2)Declared the app key as global variable,

kiip_app_key='app-key from kiip site';

3) And intialized the kiip instance and invoked the method.

                var kiipInstance = new Kiip(kiip_app_key);
                kiipInstance.setTestMode();
                kiipInstance.postMoment('received offer');