Pattern problems in SolidWorks

Hi,

Recently I have encountered the following problem:
I have made an assembly (a pretty large one) and whenever I open it, some bolts and nuts in a sub assembly are suddenly moved to another position (see picture). It seems like the direction of the pattern has been changed for some reason and when I try to move them, it says "fully defined" so I can't change their position. This also affects the drawing.

When I open the sub assembly, everything is on it's place and everything looks just fine. When I edit the pattern feature, nothing seems to be wrong at all. When I turn back to the full assembly, all the bolts and nuts jump back in the correct position after clicking rebuilt. When I open a different configuration, the also jump back in the correct position. But to make hem jump back, I have to go trough all the steps that I've just mentioned every time whenever I open the assembly.
Is anyone familiar with this issue? Thank you in advance.

Best Regards,

Ersin