Udemy — course purchase failed but money debited

I purchased a course from udemy using kotak mahindra bank debit card but when i entered the otp the transaction failed. Amount got deducted from my account but the course was not purchased.
Since i urgently needed the course i purchased it again using paypal and this time it went through. So i would very much like a refund.
Ref id :[protected]
Date and time : - 18 march 2020 8:22 pm