Update app.py

app.py

@@ -196,7 +196,7 @@ if prompt := st.chat_input("How can I help you today?"):
     if "audio" not in st.session_state:
         st.session_state.audio = False
     
-    choice = st.radio("References and TTS",["Reference" , 'TTS'], index=None)
+    choice = st.radio(label ="References and TTS", options =["Reference" , 'TTS'])
 
     if choice == 'Reference':
         with st.sidebar: