Irish naturalization query

Hi all, I have applied for Irish naturalization they sent my passport and asking for explanation why my passport is not signed by me .it was simple I forgot to sign but I travelled on this passport atleast twice and no one at airport or immigration asked me .anyone faced similar situation any suggestion how to give explanation ? Any help will be appreciated thanks

Well you give thm the same explanation the one you jus gave us .. and thats what the truth is .. you can send thm an email if you don't wana write a letter ..
I hope i have answered your question