form and subform_problem when update the link field then the subform lose his data

[freedemi]

Hi,
I have a form with a subform in access 2007.
When i edit some fields in mainform everything was ok. The problem is when i change the value of primary key field in mainform lets say (id) field, then in the subform the link field (id_subform) changes with the value of mainform (id), but all the other fields change to null vallues, so it loses the previous values. This happen only in subform, while in mainform the vallues remain with the (id) value.
Thanks in advance.

[Mihail]

Why you need to change the value for primary key ?
Any way... try to requery the subform after you make this change.