Invoke-IntersightPatchDocument fails when attempting to tag a Chassis

[zj-92]

In attempting to write a simple function to Tag objects in Intersight via PowerShell, I've encountered an issue with Chassis.

Using the example provided here, I've created the following JSON string for use in Invoke-IntersightPatchDocument:
$tagsToAdd = '[
{ "op": "add", "path": "/Tags/-", "value": {"Key": "' + $TagKey + '", "Value": "' + $Value + '"} }
]'

I then use $TargetDevice | Invoke-IntersightPatchDocument -JsonPatchDocument $tagsToAdd - this works as expected for Fabric Interconnects, Server Profiles, and Blade/Rack Servers. However, attempting to use this same method to tag a Chassis object I am met with an error:

Is tagging a Chassis via API unsupported, or is my Patch Document malformed for the Chassis specifically?
For reference, when attempting to tag the Chassis objects I'm using
$TargetDevice = (Get-IntersightEquipmentChassis -Filter "Moid eq '$DeviceMoid'").Results

[dsoper2]

@Ghufz Can you check if this is a back-end issue? I'm seeing the same thing so looks like something that needs back-end support.