Changing Byline Verbage

This is usually something that’s set by the theme. What theme are you using?

I’m using the Extra theme by Elegant Theme (Divi).

Moved to Fixing WordPress, this is not an Everything else WordPress topic.

For pro or commercial product support please contact the developer directly on their site. This includes any pre-sales topics as well.

https://www.elegantthemes.com/contact/

As the developer is aware, commercial products are not supported in these forums. I am sure they will have no problem supporting you there.