In order for your dealer to be able to change your notifications, they need to have a FLEET account. Fleet is a dealer management tool allowing management of all their consumers from one web app.
Once they have a Fleet account they can connect with your device, and then they can manage your notifications.
The Fleet tool is available only to authorized Generac dealers the process for setting up notifications through this tool is considered privileged information.
Below are graphics that show what the dealers will see through Fleet tool regarding notifications.