I think you should reconsider the styling and restructure the iframe by putting:
<iframe src="https://open.spotify.com/embed/album/6PacuyET9wu53oPnOCH1hB" width="300" height="380" frameborder="0" allowtransparency="true" allow="encrypted-media" style="float: left"></iframe>
Also you can use the Figcaption property of css if you want to place the caption just on the bottom/top of the embeded thing.
<figcaption>text</figcaption>

As user4642212's comment, the styling is invalid.
Use this instead:
<iframe src="https://open.spotify.com/embed/album/6PacuyET9wu53oPnOCH1hB" width="300" height="380" frameborder="0" allowtransparency="true" allow="encrypted-media" style="float: left"></iframe>
[CodePen](https://codepen.io/Lundstromski/pen/GRqJOzx)