I have no sound when I receive messages. All other sounds work and the badge notification works along with the AOD screen notification. I tried the "Smart Things" fix and all others listed to no avail....
have you checked in Messages settings to see if Notification sounds are turned on
Open Samsung Messages then click the 3 dots on the right then click settings then Notifications then click on General Notifications and see if theres a Sound listed if not add one then go back and click on new messages which is right below General Notifications and see what it has listed
that is odd that its not playing the Notification sound for new messages i'll have to check around on that one