TrackEvent returning undefined

I have installed matomo and I am trying to trackevent, it retuns 302 status code.

p = Piwik.getTracker(url, site_id)
p.trackEvent('test-category', 'test-event') returns undefined. The network call is 302 status code.

http://analytics.ehqstag.com/?e_c=test-action&e_a=test&idsite=6&rec=1&r=140613&h=14&m=34&s=29&url=http%3A%2F%2Fdev.ehq.test%2Ffirst-project&_id=d7117e50b06676ec&_idts=1526548159&_idvc=3&_idn=0&_refts=0&_viewts=1528966641&send_image=1&pdf=1&qt=0&realp=0&wma=0&dir=0&fla=0&java=0&gears=0&ag=0&cookie=1&res=1920x1080&gt_ms=4763