Hi I am getting a message saying SERCURITY ALERT Another app on your phone may be trying to pose as the app you are currently using. The malicious app cant access your account, but linking to dropbox has been disabled as a precaution. Please contact support@dropbox com.
You might be getting this error messages because there could be two apps on your phone with the same name, and both are trying to connect to Dropbox. This can happen with free and paid versions of whatever app it is.
could you check if you've recently installed an app with the same name and try to uninstall it, or the other copy?