In the Unity 2022.3.11 patch notes it states that com.unity.services.vivox is no longer available. Where do I get the package now?
You can select add by name and use: com.unity.services.vivox
That’s what I did
The v16 package was initially released as a preview package which introduced some difficulty in locating the package for many people. Installing as KilThrall mentions is the way to go for the preview but we will be bringing v16 out of preview with our next release in mid-December. From there it will be discoverable again.