I paid this course on 5/16/2017, but today i try to access to review this course, but it need pay

hi, i paid this course on 5/16/2017, but today i try to access to review this course, but it need pay again, please clarify, thanks for help 
here is payment info, 

Merchant Reference Number : 121389
Course : Statistical Arbitrage Trading

Customer Name : mark zhang

Hi Mark, 



We checked our backend for any issues, we didn't find any. We believe you had raised this query on June 25, 2017, as well. 



As stated earlier, the course is associated with your markzhang2000@yahoo.com email ID. All accounts on Quantra are identified using the user's email address, as a result, the purchases made are also identified and associated using the email address. In your case, the payment for 'Statistical Arbitrage Trading' was done from (markzhang2000@yahoo.com) email ID.



We request you to kindly log in to Quantra using your registered email address. And you should be able to access the mentioned course. 



I hope this information solves your query, do let us know in case if you face any difficulties. 



Thank you.