Issue in PO approval

There is an issue in Purchase Order Approval for Order Type " O4" and "O5". The PO approval process do not move as per approval level setup.

E.g. In Approval Level Setup table F43008,

Order Type : " O4", Approval Route Code : 10000483, Approval Limit : 1, and Person Responsible : 10002688

In Held Order Table F4209,

Approval Route Code : 10000483, Order No. 13000219, Order Type : " O4", Person Responsible is also shown : 10000483

accoding to Approval Level Setup Table (F43008), the person for resonsible should be 10002688.

Thanks in advance, pl. help in this regard