Mr D Food / Mr Delivery – Fraudulent activity on my mr d food app

I was alerted y my bank that a transaction of almost R 700 went of my account for mr d food. I immediately cancelled my card and contacted mr d food who told me my bank will investigate there is nothing they can do. I want to know how the thief got access to my personal bank details and cvv number from your app if i dont save those details. I have to complete it each time i use the mr d ap.

I have sent numerous emails but no one responds i keep getting a mail that says someone will contact me but never do. The fraudulent order number GROC209478037