Tik Tok Shop issue

Hi guys. Last week I started a Tik Tok store. sells have going ok until 48 hours ago I received a order of 17k, which is more than 4x the cash flow I have. There are no tools to cancel the order and refund the client, furthermore, the client does wish to be refunded despite of my explanations and even threaten to sue me.

Costumer service is crap, you could talk to a concrete wall and the effect would be the same.

This seems very irregular to me. Why cant I deny an order to my shop? Or why the client does accept a refund and go somewhere else.

Is this a scam?