If you make sure your music collection is stored in public playlists, you can visit your old account with your new account and grab all your songs from there. You’ll be able to visit your old account by putting the following string in the search bar: spotify:user:username
Don't forget to replace username with your own username which should be a number if your account has been created via Facebook. Oh and by the way, If you want to use the same email address for your new account, you'll have to close your old account. You'll have 7 days to visit your old account and find your music there. You’ll also need to cancel your subscription on your old account, in case you have a Premium account.
Hope this helps! Let us know if you have further questions.
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