If you are unable to regenerate an allocation session when using the option to Deallocate it is because the original allocation was system written and across multiple accounts.
When a user creates an allocation session it cannot contain multiple supplier or customer accounts, however, some sessions that are system generated, such as billback, commission, BACS and direct debt are across multiple accounts and because of this, cannot be regenerated by the user.
If the allocation contains only one account it should be possible to regenerate the allocation session when deallocating.
