Chinese competitor buyer message?

I received a buyer message at roughly 430 am. The FBA shipping address is in Indiana but shows a chinese billing account tied to the order (on the order detail page).

The message itself is very lengthy and detailed. It basically describes how the product goes against everything as I described it to be. The email quotes multiple bullet points from my product detail page and claims it is not as described and the product is unusable.They are requesting a refund.

I haven’t responded to the email or issued a refund. My first instinct is to report the message to Amazon.

I feel that it is a chinese competitor, but I can’t quite wrap my ahead around what their intentions are.

Thoughts? Advice?