Downloaded ringtone

[AC Question]

I had a downloaded ringtone on my Galaxy 6S phone for WhatsApp and messages. It has now disappeared off the list for messages and I don't know why. I've searched in notifications and sounds but it is not there. It is however available on ringtones and WhatsApp.
Maggie

 

[B. Diddy]

Welcome to Android Central! Where did you download it from? Did you use My Files to copy it to the Notifications or Ringtones directory?