Sorry, I done it , but if someone thinks is not the right way, please,let me know...
I release the formset in the unload method of the main form
release thisformset
and it seems to work

>It's the first time I'm using a Formset Object and I got into this problem :
>
>My formset is composed by one form. From This One I Programmatically add another form to the formset, If I close the First form without closing the second first (the one I added programmatically) i notice that The Formset Object still remain in memory, if I try to modify it, the system tells me that the object is in Use. I tried putting code which test if the second form exist and in that case it tremoves it from the formset, but it doesn't work.
>
>Thank You
>Alessio