GG Attempting to insert NULL into not null column

We are getting the following error from the replication process, which then abends.  Goldengate version is 12.3.0.1.6.   Both the source and target are SQL Server.  The table columns is defined as NOT NULL on both ends.  I do not understand how we could be getting this error.

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2020-02-04 14:23:14  WARNING OGG-01154  SQL error 2627 mapping dbo.OsRes_OperationResult to dbo.OsRes_OperationResult [SQL error 2627 (0xa43)]Cannot insert the value NULL into column 'Orderno', table 'QA_SISAM_EHD_PROV.dbo.OsRes_OperationResult'; column does not allow nulls. INSERT fails.

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The only unusual fact in this situation is that the source is itself replicated.  It is a full copy of the true source and then we extract 16 tables from it to the target landing zone for customer access.