Why is the reject notification not received by a representative that is FYI only in approval chain

Summary:

Hello,

we are currently facing the problem that for a manage document record approval the reject notification is not received by the one representative that is FYI only in this approval chain. The approval goes like this: the line manager is the iniator. Then, an FYI is send to the hr bp representative (worker rep.) that an approval is initiated. This fyi is received by the hr bp representative (worker rep.). Then, the work council representative (worker rep.) gets the approval/rejection info. Now, if that rep decides to approve/reject, then this notification is received by the line manager (initiator) and NOT