While trying to migrate the record using the Configuration Migration Tool, we were getting error like below in the log
ImportEntity – Result: True – Entity: transactioncurrency – Adding transactioncurrency to the reprocess List as field createdonbehalfby with value 05d52058-eb35-41e8-8af7-dfb7120c4599 – LookupEntity systemuser and Record Id 2655712b-e13b-e711-80fb-5065f38b5691 (SYSTEM) – (action:Update) failed validation for reason code: LookupRecordNotAvailable
As we do not want to migrate the createdonbehalfby field, the easiest fix for this is to remove the field from the schema.
Ideally instead of adding the entire Entity, we should select only those fields whose value we want to migrate in the Schema file.

Hope it helps..

We have run into many scenarios where a company has Office 365 and then orders Dynamic 365 from a CSP (Cloud Service Provider) and their systems end up different tenants. As Microsoft moves to the model where there can be more than one partner of record and various flavors of Dynamics 365 (Finance and Operations, Business Central, Customer Engagement, etc..), I can see this problem getting more prevalent over time.