This turns out to be a developer error and assumption.

I program with the OWNER user for connection to the database, so the drop-down list of Sequences shows the SequenceName as a non-owner-qualified version.

When changing the development connection to a program-user ( NOT the database owner ), then the Sequence drop-down list shows correctly with the "Owner.SequenceName" format.

So, when using a different user in development rather than a program-user, then this needs to be understood that the drop-down list MAY BE DIFFERENT THAN WHAT IS REQUIRED AT RUN TIME.

I would suggest that the Sequence drop-down list ALWAYS qualify the SequenceName with the owner to resolve others from this in the future.

thx.