If then else

[austen]

I am trying to set up an "if then else" field on Impromptu for an HR product called ResourceLink.Ã,  The text reads as follows:

"if (Pers Known As is missing) then (Pers First Forename) else (Pers Known As)"

For example, if the President of the USA were on our system, if his Pers Known As were missing, it would list his name as George, and if it were not missing, it would list his name as Dubya.

However, it is not working.Ã,  Ã, For staff without a Known As name, it is simply returning a blank.

Is there something obvious that I am missing?