3712400 - Error "The valuation class cannot be changed, choose 'Display error'" in Change Material app - SAP S/4HANA Cloud Public Edition

When changing the Valuation Class of a Material through Change Material (MM02) you receive an error M3368:

The valuation class cannot be changed, choose 'Display error'

SAP S/4HANA Cloud Public Edition

1. Open the Change Material (MM02) app.
2. Enter and open the relevant material.
3. Navigate to the Costing2 tab.
4. Locate the Valuation Class field and change the value.
5. Error appears: The valuation class cannot be changed, choose 'Display error'.

It is not possible to change the valuation class if any of the following already exist for the material:

• Valuated stocks in the current period or in the previous period.
• Open purchase orders or delivery schedule lines.
• Production orders for which a goods movement has already taken place.

First identify the root cause by following the below:

1. Trigger the error in the Change Material (MM02) app.
2. Hit the Additional Data button once, and it should change to Display Errors.
3. Press Display Errors.
4. This will open a new screen which specifies the exact cause of the error.

For Stock issues it is expected to return simply "Stocks already exist", however for issues with specific documents, such as Purchase Orders, it is expected to return a list of the exact documents causing the issue. See below as per Error Long Text:

• "If there are valuated stocks in the current period, user will get message "Stocks already exist.". User has to clear all the stocks."
• "If there are open purchase orders or delivery schedule lines, user will get message "Purchase orders already exist.". User can find related purchase orders after clicking 'Display Error' button. All the PO items which don't have deletion flag will be regarded as open PO though they have already been completed and invoiced. Since the status can be easily reversed back, the system only allows valuation class change if PO is deleted."
• "If there are production orders for which a goods movement has already taken place, user will get message "Production orders already exist.". Please archive these production orders."

Refer to: KBA KB0938965 - Storage Access API enablement  

Refer to: KBA KB0107848 - Error M3 368 occurs when change valuation class in transaction MM02

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