SAP Message VAL604 - Existing book value in pos crcy is not consistent with book value clean

Diagnosis
You wish to carry out a manual valuation for the position on &V1&. Toenable this, book values must have been defined in the system as atV1.
Currently the book value is inconsistent with the book value clean inposition currency. The book value in position currency is 0 and thebook value clean is not 0.

System Response
The valuation is terminated.

Procedure
Define consistent book values.