This was a temporary logo. They changed their color from "Nokia Blue" to purple (same color as 2014 Microsoft Band logo) and changed it's font to Segoe UI. It was used commonly on Microsoft Lumia's social networking accounts like Facebook.
They replaced purple color with cyan that uses the same color as Microsoft Surface and added Microsoft Logo. In October 2017, Microsoft Lumia has been discontinued because Lumia's sale had declined but in 2019, Microsoft returned to the smartphone business by unveiling their new smartphone under the Microsoft Surface brand as Surface Duo and it is running on Android instead of Windows 10 Mobile but it planned to be released in Holiday 2020.
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