Returned-item dispute denied after buyer reports no refund

Walmart kept my returned item, refused refund, and PayPal denied my dispute — what now? I returned part of an order to Walmart over a month ago. My FedEx tracking shows the package was delivered to Walmart's returns address and includes Walmart's item number, but I never got a refund. I contacted Walmart customer service through chat multiple times. They said they'd escalate it to the billing department, but the refund was later denied with no real explanation. I filed a dispute through PayPal with the FedEx tracking as evidence, along with the Walmart order…