I keep receiving the following error message when attempting to clear:

"Challenge Not yet complete... here's what's wrong:  Could not find notification on dashboard. Please check the requirements again." 
(Task - Create a notification to alert you when lost opportunities exceed a certain amount)

The alert is created and set to run. When you Save and Run the alert, it disables it for some reason and you can't see it as a widget in  the Notification Tracking section. When you Save only, it stays active and displays the widget on the Wave Analytics home page. It doesn't display on the Oppty Details dashboard though.

Any thoughts? I'd like to complete this trail and progress to the next part of the project.

Our customers are receiving the following error in the Koa template when trying to post a case comment from the community.  It shows in a little white bar at the top of the community page.

"Uncaught error in actionCallback: this toggleMessages is not a function"

create an Apex class that inserts a new account named after an incoming parameter. If the account is successfully inserted, the method should return the account record. If a DML exception occurs, the method should return null?
The Apex class must be called 'AccountHandler' and be in the public scope.
The Apex class must have a public static method called 'insertNewAccount'.
The 'insertNewAccount' method must accept an incoming string as a parameter, name the account after the parameter, insert it into the system and then return the account record.
The 'insertNewAccount' method must also accept an empty string, catch the failed DML and return null.