3795803 - Error "The costing lot size must not be smaller than the price unit" in the app 'Manage Product Master Data' after upgrade 2608

• When editing the product in Manage Product Master Data (F1602), a warning is displayed indicating that the costing lot size must not be smaller than the price unit. When attempting to save the changes, the warning becomes an error and the product data cannot be saved.
• The exact error message is: “The costing lot size must not be smaller than the price unit.” (Message No. M3406).
• In Manage Material Cost Estimates (F7650), when creating a new cost estimate, the system uses the price unit quantity as the costing lot size, instead of the previously maintained smaller costing lot size.
• Costing runs executed before the 2608 update were processed successfully with the smaller costing lot size.

SAP S/4HANA Cloud Public Edition

1. Open the Manage Product Master Data (F1602) app.
2. Edit a material where the maintained costing lot size is smaller than the price unit in the valuation area.
3. Observe the warning: “The costing lot size must not be smaller than the price unit.” Message no. M3406.
4. Attempt to save and observe that saving is blocked with an error.
5. Open the Manage Material Cost Estimates (F7650) app.
6. Create a new cost estimate for the same material (with a valid plant and costing variant).
7. Observe that the system uses the price unit quantity as the costing lot size instead of the maintained smaller value.
8. Compare with previous costing runs from before the 2608 update that used the smaller costing lot size.

• There was previously a gap in the validation logic that allowed a costing lot size lower than the price unit to be maintained. 
• With the 2608 upgrade, this validation was corrected.
• Therefore, the system now prevents combinations where the costing lot size is lower than the price unit.

1. This behavior is by design after the 2608 update
2. Identify materials where the costing lot size is smaller than the price unit in the valuation area.
3. Update the material master so that the costing lot size is greater than or equal to the price unit.
4. Save the changes in 'Manage Product Master Data'.
5. Recreate material cost estimates in 'Manage Material Cost Estimates'the system will process with the supported values.

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