Weak security and refusal to reimburse

After just I opened a business account and made a deposit I was a victim is SIM swap *****, the *****sters gained access to my account and took money form my account. Went an open a ***** case at FNB the said they will investigate and come back to me . After their investigation the refuse to refund my money back. Just imagine a new account less than a month old . Am very. Sceptical about continuing with it as these might happen again and there would be no one to help me😭