So I believe what you need to do here is merge the two patients MRNs together since one is already in use. Do you have a FilePatientMerge_CMS message definition/interface built in ConnectR yet? If so, it is most likely waiting for an ADT^A34 message. If you do not have a FilePatientMerge_CMS interface you can do this manually in the Patient Merge tool but I would blank out fields 92-95 first in order to have the new registration post successfully. Once the two MRNs are merged the FilePatient call should work without issue.
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