The following steps apply when Messaging is set as the default app.
From a Home screen, swipe up to access all apps.
Tap Messages.
From the Inbox, touch and hold the message containing the ringtone.
Tap the Save icon . By default, the sound file is saved to: Internal Storage/Download. To view the sound file as a ringtone option, it can be moved to: Internal Storage/Ringtones via File Manager. To set the ringtone, refer to Set Ringtones.