3662468 - Error ML4HMASTER150 when Cancelling Confirmation - SAP S/4HANA Cloud Public Edition

Error message ML4HMASTER150 occurs when attempting to cancel the confirmation of a production order, indicating "Actvitity types closed in ML. Please reverse the closing in plant &1". 

SAP S/4HANA Cloud Public Edition

There is a costing run related to the activity type in a closed period. The posing information can be checked in the app "Display Line Items - Production Accounting", showing relevant activity types for the closed period.  

Re-open the affected period to resolve the errors if necessary.
If it's decided to re-open the period, reverse the post closing step of actual costing runs. 

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