In order to merge your accounts, you need to open your account settings and click the Merging accounts tab or follow the link https://musescore.com/user/settings/profile/merge-accounts.
As soon as your accounts are merged, you'll be able to manage all your scores from one place easily.
Please note that this feature does not include subscription transfer. In case you need to transfer the paid PRO membership, please, contact MuseScore Support and send us proof that you are the owner of the account, such as a receipt of purchase.
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