Cancel Confirmed TO

Hi All,

I have a problem to cancel my confirmed TO.

Because this is a Posting Change with HU, so we cannot use SAP standard transaction LT0G to cancel the TO.

I've tried also to delete assignment, but got an error "storage type 001 does not allow repacking - HUs cannot be changed".

As i know if we can delete assignment,

then we can "pack" and "copy pack as qty as del qty".

After that we can proceed use LT09.

But right now i'm stuck.

Need advise from the expertise.

Thank you very much.....