diff --git a/fern/quickstart/phone.mdx b/fern/quickstart/phone.mdx
index bfc579be..48225691 100644
--- a/fern/quickstart/phone.mdx
+++ b/fern/quickstart/phone.mdx
@@ -126,7 +126,7 @@ vapi assistant create
               // Configure the voice
               voice: {
                 provider: 'playht',
-                voice_id: 'jennifer',
+                voiceId: 'jennifer',
               },
               // Set the first message
               firstMessage: 'Hi there, this is Alex from TechSolutions customer support. How can I help you today?',