In a http PATCH request, we can't use simple lists.
for example this rest call will fail:
http://10.200.2.2:8181/restconf/config/network-topology:network-topology/topology/topology-netconf/node/ciena01/yang-ext:mount/ciena-mef-fp:fps/ PATCH ContentType: application/yang.patch+json
{
"ietf-restconf:yang-patch" : {
"patch-id" : "0",
"edit" : [
{
"edit-id" : "edit1",
"operation" : "merge",
"target" : "/ciena-mef-fp:fpciena-mef-fp:name='vlan-VLAN#3223-LAGtest'",
"value" : {
"fp" :

}
}
]
}
}

because "classifier-list": ["clsfr_v3223"] is a simple list, and the comtroller expects a json object inside the string and not a simple type like the string.
This happens only on PATCH requests.