Letter of executorship

I have been sending email for a while to someone to give some advice. I have called various numbers at different times and NO ONE picks up at all, like why not? My niece, who is my power of attorney, can collect the letter of executorship of my late husband on my behalf, I am unwell and cannot do this trip. I mailed the proof to show that I am unwell and that I am executor, I just need a copy to close my husbands estate as he is part of the home loan we took out , but the bond is paid up, now I need this doc to close the account, someone help.