I hope it gets sorted out and I'm sure it will. The bank has to be sure that on the balance of probabilities it was fraud because overall fraud costs have to be met in effect by all customers and shareholders so they can't just take everyone's word for it that it was fraud.
The bank may also be aware that some students have tried scams where they give a card to a friend who is travelling home one weekend to another part of the country, get them to withdraw cash, and then report a phantom withdrawal claiming they never left town.
I'm not implying that's what's happened here, just saying why banks have to be careful.
I was a victim of an online credit card withdrawal and I got money back, so you'll be okay I'm sure