fnd_program.delete_parameter is not working as expected

hello,

we are trying to delete a concurrent program parameter from the backend; we have used the API fnd_program.delete_parameter. the API completes successfully, we checked that the parameter has been deleted (checked the front end and the back end); BUT when we run the concurrent program and click on submit we get an error saying that "parameter xyz is NULL" as if the concurrent program is still expecting this parameter to be populated.

is there something else that we have to run after calling the API to synch the app server with the database??? is it some sort of a caching issue?