Code 23s are given when an order arrives short and the freight bill is marked SLC (shipper load and count), meaning it was the shipper's responsibility to load the truck and confirm quantities and the carrier did not verify a carton count.
Code 23s are extremely rare, with Walmart typically using the more general code 22 or 24.
Most often this should be disputed with the carrier rather than with Walmart. If you need a copy of the proof of delivery that Walmart signed for the shipment as short, then you could file a dispute in the Accounts Payable Disputes Portal (APDP) in Retail Link and request proof that it was signed short.
OR, dispute with the carrier and provide:
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