Steadfast refusal to take any responsibility whatsoever

Still getting the runaround with FNB refusing to engage with the matter at hand. Furthermore they steadfastly refuse to share any contact details for any senior manager to allow us to contact and address the issue. They only try random calling at inopportune times, without even the option to call back and engage with the particular person - everyone tries to hide behind anonymity, to ensure that no one can be held responsible. I expect that FNB will provide us with a person, in a specific role, with direct contact details, to allow us to properly address the issues, I refuse to engage via a call-centre anymore on this matter