Someone else has already said this but do not force us to use a number as a username, I'd like to change it to something like my email. As I've been a premium user for many years now I can't delete my account and make a new one, and since I'm paying for this service I'd love it if support could change my username.
Since your username consists of numbers, it sounds like your account was created through Facebook. Just so you know, all of your friends and followers will see your name from Facebook.
Bear in mind that the username of an existing Spotify account cannot be changed. If you decide to create a new account, a username combining numbers and letters will be created automatically. This is happening due to security reasons so each customer could have an unique username.
You will however, have a display name as well. This is the one all users will see when they come across your account. You can choose a display name in the 'What should we call you?' field during sign up. We suggest you do this on a Desktop device.
Also, no worries - you won't lose your music. If you wish to have a different username, you must create a new account and you can transfer all of your music to it. You can read more about it here.
Last but not least - it's very important that you cancel your subscription on your previous account and subscribe to Premium on the new account. If you have subscribed to Spotify through a partner of ours, you must reach out to them so they can fix this for you.
We hope this info helps.
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