When you click enter after you have typed in the chat name streamlit generally refreshes the page to load the new input of the text but now the edit_chat_name function is not called you should put the text_input outside and then store it in st.session_state and then use that in edit_chat_name if you want to not show the input_box when you are not editing the chat name you can write an if statement with the button and write the text_input inside the if and then have a nested if for that (which would get called if they enter the text_input) and then finally save the text in st.session_state and call the edit_chat_name function, Example code:-

with st.sidebar:
    ....
    ....
    if st.button('Edit Chat Name'):
        if text := st.text_input('New Chat Name'):
            st.session_state.chat_names[st.session_state.current_chat_id] = text
    ....