hHyperlinks to bookmarks work sometimes and not ot

In my site files I have a hyperlink from a 'top' gif, which sits at the bottom
of each page, on the right., which leads to a 'top' bookmark at the top of the
page. All site files were created similarly, using a template, with the
hyperlink in the template, along with a back button and a 'home' one. The back
and home always work, but some of the 'top' links work and some don't.
Illustrated by these two files:

www.teamcommunications.com/Influencing_Skills.htm
www.teamcommunications.com/Career_Development_Guidance_Notes.htm

I have detached these files from the template. The graphics won't be visible
but the placeholders are there.

I would very much appreciate it if someone could shed some light. Is there a
difference in the code which I just can't spot?!

Many thanks in advance!