It seems your application to teach has not been approved yet. You do not have a teachers profile page, so no one knows you are here to teach. Even after you are approved, you will still get all sorts of messages. I've been teaching on here for years, but still receive a ton of messages every day asking for free language exchange, or offering to teach me a language. There is nothing you can do about it, it's just part of using a website like this. You can just choose to ignore them or send a standard generic reply saying you are only here to teach, not exchange or learn a language.