Terrible service from Thobeka Sotyantya at Virgin Active

Virgin Active debited my account with R640 instead of R320 at end November. I called their call centre on 4 December and their agent, Thobeka Sotyanta confirmed only R320 was due. Thobeka requested that I send her an email showing proof of the R640 deducted. I sent the email on 4 December. Receiving no response or even and acknowledgement that my email was received, I emailed Thobeka again on the 9th and 11th December. I then called the call centre again and was told that my email had been received and was being worked on. To date I have still never received a response from Thobeka to my emails, and still no response as to why I was debited with twice the amount I owed.