2838582 - Error M7115 posting difference into previous period

A Physical Inventory document has been created for one or more materials. When trying to post the count difference into the previous period the error message 'Back-posting only poss. w. same val. class' (M7115) occurs.

SAP S/4HANA Cloud Public Edition All versions

1. Open the tile 'Create Single PI Document'.
2. Enter the required data and save the PI Document.
3. Open the tile 'Enter Inventory Count'.
4. Enter the required quantities and save the update.
5. Open the tile 'Post Physical Inventory Document'.
6. Set a posting date in the previous period.
7. Enter a difference reason and press POST.
8. Error 'Back-posting only poss. w. same val. class' is raised.

Changes have been made to the valuation class of the material. The system checks the valuation class of the current and previous periods, MBEW-BKLAS and MBEW-VMBKL. 
If a difference is found the posting is stopped with this hard coded error M7115, to avoid database inconsistencies.

This is not a customisable message and it cannot be avoided. Please post the difference into the current period.

MBEW-BKLAS, MBEW-VMBKL, MARV, MI07, MI20, MI04, physical inventory document, previous period, Enter Inventory Count, Post Physical Inventory Document , KBA , MM-IM-PI-PI-2CL , Physical Inventory (Public Cloud) , MM-IM-PI-PI , Physical Inventory , Problem