@Irma313 That is a text "notification" only. It does exactly as intended, as it's to notify you that there's information you need to know about on the AirBnB platform. When you get that notification, either open the app on your phone or log in on your computer. You should also get an email depending on how you've set up your notification preferences.
As to the other issue, you should probably delete the app and reinstall, and then make sure you're signed in the the proper credentials.