I don't know how much help it will be but since you have the manager's name and I'm certain you know the store's location, call Walmart's customer service number (it's on their corporate website) and lodge a complaint about Matt's lack of assistance and the chronic problems with the electric carts. Do this every time there's a problem. It'll get pass to the regional manager who, trust me on this, will look into it. One thing corporate is big on is making things right with the customers.