Chatbox, show title when user key message on input box on Mobile phone

Dear friends,
Now I create a chatbot and I set screen max 600 will show chatbox for full screen.
it’s work.
it has Title, Message box and send message form.
normally it will show all but when I try to put any message, the screen can’t show title
Pleae look at my attached file for detail
This is the normal show when I don’t key any message
Will be like this when I ket any message. the mobile phone’s keyboard will appear. then I will not see title bar
So My question is:
How can I show title bar when I key message?

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