Why would a manufacturer buy their stuff back from my Walmart account?

I have a distributor that I buy some branded products from. I sell on multiple platforms so I only put 5 of one of my items up on Walmart and the manufacturer bought 4 out of the 5. There’s 2 variations (5 each) and they only bought 4 of the same variation. I noticed it was a business address which is weird for me so I looked it up and saw that it’s the manufacturer’s office. They bought 1 item and a few days later bought 3 more. Any idea why?