FNB couldn't help reverse *****ulent money

Hi.

I was using Facebook page to run ads for my business, sadly my page got hacked and automatically deleted and I was no longer receiving service from them. My business page was linked to my FNB card and that's how they manage to ***** me and took R5700 without an agreement and the bank says they won't be able to reverse that amount back to me, how so because I was no longer using Facebook online service because my account was hacked. Please I need help 🥺