there was a 'sound' option for my last phone but I can't find it on my vivo 7+. are you reffering at the 'volume' option perhaps? tried it didn't work, check the pics
https://drive.google.com/file/d/1_39IaOrXHGYSKmNCDaLBVSeGi7sHubWv/view
Just got a vivo 7+
went to settings>volume> there I try to set up my ringtones
There was no problem setting up custom ringtones for messages and call ringtones.
But for notification ringtones there was a problem. There was no option to choose a custom ringtone unlike for messages and calls...