Welcome to the Community page,
Have you tried uninstalling the app and reinstalling it again and see if them messages and accounts go away for you if you no longer have them in your account.
Yes, it happens on my ipad as well as an iphone and my android phone. I have deleted the app off all devices and re-installed and that is no good either. These notifications must be being held within quickbooks online at the server end, as each time I re-install there they are again (and on multiple devices).
Why isn't there a simple swipe left to acknowledge and delete?