Change value of query field with code?

[Orcanut]

I have a form based on a query "Notation Payment" with a field Authorization. This form runs a macro which returns a new value for the Authorization field. I can physically change the Authorization value in the Query Builder screen if I run the query but the following code:
" Authorization = moCDCAResult.AuthNum " precipitate the following error: "You can't assign a value to this object"

If I can physically change the value of a Query field I must be able to with code as well but I appear to be stumped.

Any thoughts most welcome.