Complaint Review: Walmart

I worked 2+ years for a retired blind college math teacher as a personal assistant.
I manage his purchases. 

March 25, 2020 we ordered the Victor Reader Stratus 12 Daisy MP3 Player from Walmart online. It was a long while before he could try it.
It failed to play Daisy material that his government issued player could. The files 'were' Daisy, as I transferred the files myself onto his flashdrives. 
On the last day allowed by Walmart to qualify for a refund, I got a receipt for it when I dropped off the item at a FedEx station. 

For the following months I called the local Walmart, who said Walmart.com was a separate entity, and I tried the tol free phone number they gave me. I used the automated system, but could not reach anyone. I left 2-3 messages. Waited about 2 weeks. No response. I searched their website for a return dispute. I filled 2 reports over time, but still got no response! I re-read everything. We "definitely" sent the item back on time, in the original box, and undamaged in any way. 

This is outrageous!

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