Hi Christine,
This message happens when the system tries to calculate a conversion but doesn't find the expected rate.
It could come from the GL currency or a ledger currency (legal or another one where the matching is propagated); you have to identify where this conversion comes from and which currency type is used to check en feed if needed the currency rate in the COURDEV function (Common data>Common tables>Currency rates).

Hi Christine,

If Vincent's suggestion helped you resolve your issue, please mark the answer with "verify answer" to assist others we similar issues in the future.

Thank you,

Pam