ClickBank error or Activ Ebook error ?

I have an affiliate  link in an ebook to a ClickBank
site which sometimes works and sometimes fails with
the error message "Bad Gateway"

When this occurs the Url starts

http://[={zznickn.cb.kount.com/hop/1066339250/supertips/0/0/..

The 'zznickn' is part of a variable I use
in the link in the book viz

href="[={zzpidstart}][={zznickname}&pid=6]"

My question: surely the variables zzpidstart,
zznickname should be resolved BEFORE the Url is sent
to the browser

Problem was that I have put the final "]"
in the wrong place