The "name" of your ad is really your Link title. A Link is the landing page that the ad points at. To change it, open the Link, hit edit, and update the title.
Running your own Meta ads
The Link title is purely the landing page's name. It doesn't sync back to Meta, so renaming it won't change the name of any campaigns you've already set up in Meta Ads Manager. You'd do that over there. Renaming here just changes what visitors see on the page.
SubmitHub Ads (managed)
If we're running ads for you, we generally recommend against changing the Link title. When we set up your ad, a lot of the copy references the Link/landing page title. Change it from "Study Beats" to "Music for focusing" and suddenly the ad copy we built around the old name reads weird.
We don't block the change, but you'll see a warning modal asking you to confirm, and we get an internal notification so we can flag anything obviously off. If you really need to rename it, keep the new title close to the old one. For major rewrites, reach out to us first so we can rework the ad copy too.