Unauthorized online transaction

I have been the client with FNB for years now and this morning I woke up with a text saying there's a reserved R2313.54 Transaction from Courcehero that I know nothing of and never authorized. I then logged into my chats to speak to one of the consultants by the name Of Lesego and confirmed the name of the transaction but failed to give me full details. She said it was an online transaction but could not assist further kept on referring me. If FNB is not going to assist thier clients with such ***** then this means we must move to other banks. I spoke to her twice and now I have no money to pull me through the whole month while am told to wait for 15 days.