EDI validation problem

I am running Connector Server 4.6, for an inbound edifact 96A invoice. I have a flow that errors with com.wm.app.b2b.server.ServerException:Input validation for service failed:myservicesname: /string VV-001[B2BCORE.0082.9025] Missing Object.

when I run pub.schema.validate my only error is on /UNH VV-003 [B2BCORE.0082.9028] Dimension mismatch, Single item expected.

BUT when I run the service in Trace it does NOT error.

Any clues?, is the validate message the same as the exception, and why does it run thru on trace but not run. My service is starting with a restorePipelineFromFile, when I saved it (using Run) it did not error. When I disable the validate step I still get the exception

any pointers greatly appreciated