This applies to those who use Landed Cost Wizard.
A critical bug was found in the Landed Cost Wizard: When Landed Cost Wizard was used to add a row in Taxes and Charges table of Purchase Receipt rather than correct an existing charge value, it failed to update the valuation.
The bug seems to have existed since September 2013 and was unnoticed till today. Alas, a clean patch is not possible for this bug, since most of you would have closed your financial years.
You will also need to verify the valuations manually and create correctional entries via Stock Reconciliation and Journal Voucher.
Please update your ERPNext instances to the latest release v3.12.0.