As you might already be aware, you can change your username once every 30 days
. We can't tell you here on the forums, because we'd need to go through a verification process with you to access your data, but my teammates on our direct communication channels will be able to tell you when you last changed your username. Please contact them at the links below, and be sure to include your Ubisoft Connect username or email address in your message
Good luck with your new name!