Streamlit elements disapper from screen while using chat_message chat

Using Streamlit
, ,
1

Hi everyone,
Streamlit element disappears from screen while testing chat_messages but messages are not affected, anyone kindly assist. this is my code:
import streamlit as st

#Initiate
if “messages” not in st.session_state:
st.session_state.messages =

#Display
for message in st.session_state.messages:
with st.chat_message(message[“role”]):
st.markdown(message[“content”])

user_message = st.chat_input(“Type your message here…”)

if user_message:
# Display user message in chat message container
with st.chat_message(“user”):
st.markdown(user_message)

# Append user message to session state
st.session_state.messages.append({"role": "user", "content": user_message})

# Display assistant response in chat message container
with st.chat_message("assistant"):
    response = user_message
    # response = llm.invoke(user_message).content.lower()
    placeholder = st.empty()
    if "paris" in response:
        placeholder.metric(label="Temperature", value="70 °F", delta="1.2 °F")
    else:
        placeholder.markdown(response)

# Append assistant response to session state
st.session_state.messages.append({"role": "assistant", "content": response})