Missing Yearly Archive Pages

For some reason when I click a link (or enter the address into the browser) for certain years the ‘yearly archive page’ is not found. This doesn’t happen for all the years. Just some. If I click the link in ‘collapsing archive’ plugin for the year, some are not there while others are.

I don’t know where to begin fixing this. My blog exported into wordpress.com via xml has none of these problems.

my blog is
https://www.mundoblaineo.org/blogpress

here is a link which works
https://www.mundoblaineo.org/blogpress/2012
and one which doesn’t
https://www.mundoblaineo.org/blogpress/2006

hope someone has some ideas.

blaine