customize columns on access database

I have a populated  a access database when I set up a mail merge program for sending out newsletters. At the time I only used Name, Surname and email adress. I went to customize Columns and deleted the other options of adress etc.

I would uke to re-installl these columns , but the program does now not allow this application _ 'customize columns' is 'grey' so unavailable

How do I add these columns back ?

On the Access help sites, when following instructions these added columns get a "syntax value" and you cannot add an address ???

Please help , I must be able to add these columns back and populate the names with adresses and phone numbers