Embed Report - Subscribe API called multiple times in browser

Hi,

Once Power BI report embedded in our application, in network i see multiple scubscribe calls been triggered and all of them get cancelled after waiting for long time. Can any one explain me on why the subscribe call is triggered and on what basis it is triggered? Also it is getting cancelled automaticlally and seeing network status as cancelled.

Subscribe API - https://wabi-west-us-redirect.analysis.windows.net/powerbi/refresh/subscribe

Thanks in Advance.