SAP MM ME22N to change PO quantity and get error msg - System status CLSD is active (ORD 600120) –

ME22N to change the PO 4500000006,

Try to change the quantity from 2 to 20,

Got the error msg --- System status CLSD is active (ORD 600120) ---.

The reason is that the internal order assigned this PO was closed,

The system status of internal order 600120,

2016-09-22 In Wuhan City.