No fixed or variable value field was specified

What causes this issue?

Operating concern &V1& is active for both costing-based and
account-based CO-PA. Thus when you execute the cycle, a value field
needs to entered for both the fixed costs and the variable costs,
otherwise only the fixed costs or the variable costs are updated in
account-based CO-PA.

System Response

If both forms of CO-PA are active, the cycle cannot be executed.

How to fix this error?

Enter a value field for both the fixed and variable costs.

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.