Captions not appearing

I have used this code [video src="http://qikam.com/testdemo/calculationkey.mp4" captions="http://qikam.com/testdemo/calculationKeys05.srt"]

The video is playing but caption is not appearing. Can you help me with?

https://ww.wp.xz.cn/plugins/media-element-html5-video-and-audio-player/