I am really sorry for our inconvenience. We are trying hardly to find out a way. I will request you to please give us time. You are waiting long days. Please wait another couple of days. In this time I will find out a solution hopefully.
I have setup Test Secret Key, Test Publishable Key and Test Client ID from my own stripe account.
Also, I have created a seller account and added a product. After added a product I have purchased that product for test purpose and an order has been made successfully. I have attached a screenshot. Please check below: