Span tags showing on page

I’m seeing these span tags appearing – I’m guessing it is a conflict with my theme Daniel theme by Web Savvy Marketing on the Genesis framework. I’ve worked a lot with Genesis sites and haven’t ever seen this behaviour.

<span data-post_id=Person's Name : Person's Position">

What do you think could be causing this?

https://www.ads-software.com/plugins/simple-staff-list/