Unauthorized debit order

I received an SMS from my bank to say African Bank authorized a debit order on my account for personal loan That I did not even apply for. I also checked on my banking app and indeed the debit order was there on my account which i had to suspend the debit order as i did not authorize it. When i called African bank no one could provide me with an answer but was told that they will lodge a case. Am so dissatisfied and worried about my credit record because of such negligence.