I have recently purchased an Oculus Rift S and it is now discounted by $100. I have gotten the run around from Sales and Support since the item is out of stock.

There is no where in the Terms of Sale stating they cannot refund me the amount even if the item is out of stock. This does not seem right by any means.

https://www.microsoft.com/en-us/storedocs/terms-of-sale

A line from their terms of sale:
However, if we lower our price on a device within 30 days of your purchase, we will honor the lower price. If you notice that we have lowered a price on a device you recently purchased, just bring your original sales receipt back to the place of purchase or contact Sales and Support, as applicable, and we’ll gladly issue a refund or credit for the difference (if you paid with a credit card, you’ll need to use the same card).