[.NET Journal] Working with objects

Hello Community,

I spent over 10 hours of my life trying to get working with NXObjects generated by a feature builder on NXOpen Journal with VB code.
To be more simple, I would like to explain my example:

1. Insert a Datum CSYS --> done;
2. Create section 1 --> done;
3. Extrude the section 1 --> done;
4. Remove parameters of the extrusion 1 --> done;
5. I see Body(1) on the Part Navigator, as expected;
6. Create section 2 --> done;
7. Extrude the section 2 --> done;
8. Remove parameters of the extrusion 2 --> done;
9. I see Body(2) on the Part Navigator, as expected;

Body(1) and Body(2) are two sheet bodies and my goal is to merge these two unparametrized sheet bodies in order to obtain only one merged sheet with the sew command.
To do this I recorder a new journal with the sewbuilder flow but it only works with the Ctype(FindObject...) command. When I edit the line to identify the two bodies Body(1) and Body(2), the journal stops working.
I declared B1 as Body(1) in this way:

RemoveParametersBuilder1.commit()
Dim B1 As NXOpen.Body = RemoveParametersBuilder1.GetObject()

In the same way (changing the index 1 with 2) I declared B2 as Body(2).

What is wrong? I don't find anything to be helpful.
Thank you in advance,

kalo86