Custom ringtone notifications for revolution by lg

I've been trying to get my phone to use a custom notification for when I get a text message. I can get the file into the ringtones folder, but it wont show up in the "Ringtone Notifications" folder. The way I got it to use as a regular ringtone is by adding the file into my music folder, then clicking on the use as ringtone button after I hold my finger on it for a second. Any suggestions on what I can try next?

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