If it's coming off I'd think about replacing it for the earlier and in my view nicer badge.
I did that on Bumble Steve, and it looked much better. There's a How To buried in 2013/4.
I tried the same thing with my current Plus 4, but the badge was fitted with the paint still soft, and it left an outline which the earlier badge doesn't cover.
So without some paint rectification, it was a non starter.
