How to unset Project Area List, Team Area List field using OSLC Rest API.

I am trying to unset (empty) the Project Area List or Team Area List field of specific entity.

For same i executed the PUT request with URL : https://server:port/ccm/resource/itemName/com.ibm.team.workitem.WorkItem/<<entity Id>>

And passed body part keeping [] for Project Area List and Team Area List field. But it is not changing(perfroming Unset) on entity.

Body :
{
    "2:due": "",
    "1:startDate": "",
    "1:Custom_Team_Area_list": [],
    "1:Custom_Team_Area": null,
    "prefixes": {
        "1": "http://jazz.net/xmlns/prod/jazz/rtc/ext/1.0/",
        "2": "http://jazz.net/xmlns/prod/jazz/rtc/cm/1.0/",
        "3": "http://purl.org/dc/terms/",
        "4": "http://open-services.net/ns/core#",
        "5": "http://open-services.net/ns/cm-x#",
        "rdf": "http://www.w3.org/1999/02/22-rdf-syntax-ns#",
        "6": "http://open-services.net/ns/cm#",
        "7": "http://jazz.net/ns/acp#",
        "8": "http://open-services.net/ns/core/acc#",
        "9": "http://open-services.net/ns/pl#",
        "10": "http://jazz.net/ns/process#"
    },
    "2:estimate": "",
    "2:timeSpent": "",
    "2:correctedEstimate": ""
}


Please let me know, How can i perform Unset for Project Area List, Team Area List fields.