FNB throw away the title deed of my property & now I am struggling to get my property registered in new owners name

I sold my property which is bonded through FNB, in December 2018. The transaction can not be registered because FNB throw away the title deed of the property. FNB is not responding to requests to give their instructions to finally proceed with the attorney's application for the lost bond in order to register the matter. We tried several routes & there is no respond from them. This is the reason I took away my business with FNB they are useless & do not care at all!