TO_CHAR Oracle function not working with e-Text template

EBS 12.1.3
Have a requirement to develop an eText file using an .rft file
One of the fields require payment amount to be in the form $$$$$$$cc.
This can be achieved using a combination of "replace" and "to_char" to convert e.g 410.1 to 41010
The "to_char" used alone or combined with "replace" does not work.

Do you have any idea why it is not working?
The functions works when combined and used directly in toad or within a package/procedure.
However the function doesn't work when used within a template rtf file.

Have reviewed the manual - to_char and replace are xdofx functions: