FHIR Encounter update erases partOf attribute

Hello,

Not sure if I am posting this in the right topic. So please excuse me if I it is not.

I have noticed that if I try to update through the FHIR API (PUT request) an Encounter resource that is part of another Encounter, the partOf attribute is erased after the update.

Is this a bug or am I doing something wrong?

I am using the reference application.

omod.fhir=1.18.0 war.openmrs=2.1.4 version=2.9.0-SNAPSHOT

That sounds like a bug to me.