Few points needs to be understand..
1) Are you able to scan the device in S9?
2) Are you using CySmart App ?
3) If you are able to scan the device and when click on the device name for connection , what is the error reported by App ? You can see the logs in cySmart App.
4) It seems there are many problems with S9 as mentioned in this article - https://www.technobezz.com/how-to-fix-samsung-galaxy-s9-bluetooth-issues/ please check if you see any of the issues listed in this article.
5) Let me know the exact steps you are performing for the test.