You can't use accrual method &2 for accrual item type &1.

What causes this issue?

You can't use accrual method &V2& in accrual items that have accrual
item type &V1&.
In Customizing view <DS:SIMG.VC_TACE_ITEMTY>Define Accrual Item Types
</>, accrual type &V1& is set to allow uploading periodic accrual
amounts. That's why the algorithm used in the accrual method must return
the uploaded accrual amounts. This algorithm is implemented in ABAP
class CL_ACE_CFG_METHOD_ITEM_PER. However, accrual method &V2& is not
assigned to this ABAP class in Customizing view
<DS:SIMG.V_TACE_ACMETD_S4>Define Accrual Methods</>.

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?

Please use an accrual method that is assigned to the ABAP class
mentioned above. If no such accrual method exists yet, create one using
Customizing view <LS>Define Accrual Methods</>.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.