Do you mean the Registrar of BDMs in Suva? Are you writing to the correct address? They have a webpage through which you can contact them.
Otherwise Mormon Family History Centres can order in copies of Fiji BDM microfilms.
Go to www.familysearch.org, Library catalog,Fiji,vital records, general deaths, take the call number for the film of the appropriate date, and order a copy of it at your local FHC or big library.
Whereabouts do you live?
Christine