Use of Duration - Custom BO - Action

Hi All,

I'm facing an issue which is not clear at all to me.

I was wondering whether someone could explained it to me.

I created a custom BO and defined an action.

On this action, I want to create a Duration however I get the following error message when I call "Create" method (Same for method "ParseFromSting"):

==> Btw: this code works fine on an event of a standard BO (E.g: BeforeSave).

Here is my coding:

thanks in advance.

kind regards,

Andres