Walmart wants associates, not gig workers, to deliver more orders as the retailer struggles to verify the identity of its Spark drivers

Walmart CEO Doug McMillon : "We'll have associates doing more deliveries" Walmart has attracted hundreds of thousands of gig workers to its Spark Driver app.

The retailer is growing its own delivery business after ending a partnership with DoorDash last year .

Spark "is the biggest portion of our delivery business in the US at the moment," McMillon said.