How To Fix VSB406 - Quantity and value of the item must have the same +/- sign

SAP Error Message - Details

• Message type: E = Error

• Message class: VSB - Self-Billing Procedure Messages

• Message number: 406

• Message text: Quantity and value of the item must have the same +/- sign

What causes this issue?

The IDoc item has different plus/minus signs for the quantity and value
displayed.
Quantity:,,&V1&
Value:,,&V2&
An IDoc that does not identify a unique plus/minus sign at item level,
is not processed further.

System Response

The verification check ends with this message. Changes can no longer be
executed online as this is an example of quantity and value fields.

How to fix this error?

Ensure that quantities and values of an item always have the same
plus/minus sign in the EDI subsystem (converter).
These are primarily examples of IDoc fields.
E1EDP01-MENGE (item quantity) and
E1EDP26-BETRG (net value of item).
For other value or amount fields, such as conditions or taxes, the plus
/minus sign should also be adjusted. These fields are not used directly
in the processing step, however they are used in the monitor for
display.
Item quantity and item net value are used directly in processing with
the plus/minus sign provided by the EDI subsystem (converter).

Procedure for System Administrators

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

Error message extract from SAP system. Copyright SAP SE.