Error: The Supplier agreement on this contract number is invalid

The Error

When submitting products to Walmart as a drop ship vendor (DSV) you may receive this error as a description of your failed products feed: The Supplier agreement on this contract number is invalid.
Generally, this error indicates that an item has been set up in a Department for which there is no signed contract.

The Solution

Reach out to Walmart to request permission to sell your products. Walmart will send you an official agreement with a three letter code in it. This code should be assigned to your products before you submit them.