Is there a way to change a Fiverr display name (login) somehow?
You need to write to Fiverr support to request this. I am not sure if they let you change your name here once you pick one though.
No, username cannot be changed, there’s no way.
If you’re new (as you seem) you can close current account and open a brand new one choosing the name you please
And neither can you change the file name of your Gig which happens to be the original title you used when you created the Gig. So if you change your Gig’s title to say, “I will do this and that” when it originally was “I will do crazy stuff”, the Gig’s URL will still say "crazy stuff"
That can create some embarrassment.
Fiverr makes some boneheaded choices.
test post to check display name