How To Fix TU755 - Item on due date &1 cannot be unlocked as already invoiced

SAP Error Message - Details

• Message type: E = Error

• Message class: TU - Billing/Scheduling/Budget Billing

• Message number: 755

• Message text: Item on due date &1 cannot be unlocked as already invoiced

What causes this issue?

The item for due date &V1& cannot be unlocked because it has already
been invoiced or the invoice was not reversed.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.