Power BI MVC Embedding Tiles issue

Hello,

I am having issues with my embedding of tiles into my MVC5 app.

I am able to query the API, get a list of dashboards, and for each dashboard then get a list of tiles.

However when I render my partial view which contains one of more IFrames (in this case 1) that display a Tile, All that happens is the Ifram displays, showing the loading spinner, but never actually displaying the Tile visual.

I am using in this case the available Customer Profitability sample, and attempting to display the Gross Margin % tile.

<iframe width="465" height="350" src="https://app.powerbi.com/embed?dashboardId=XXXXXXXXXXXXXXXXXXXXXXXXX&amp;tileId=YYYYYYYYYYYYYYYYYYYYYYYYYY" frameborder="1" allowfullscreen="true"></iframe>

Is an example of what is rendered by my partial view (keys altered).

Have I done something wrong here? What could be the reasons why the visual never actually displays?

Thanks