Hey @A5S, it's actually really! Try the steps below.
From your desktop or mobile device:
1) Click on your Yes Crowd avatar, that'll appear on the top right of your display next to the message icon
2) From the next screen, you'll see the option to change your username
3) Delete your existing username → enter your new username → Click, "Change Username"
If you run into any issues, give us a shout! Happy to help out.
Thanks for letting us know, A5S. What would you like to change it to? We'll be able to do it on our end.