How to update status of a defect in RTC using Rest API

We have a need to update the status of the defect/observation logged in RTC. We are trying to leverage the Rest Apis published for Jazz toolsets.

URL used: https://<domian name>/ccm/resource/itemOid/com.ibm.team.workitem.WorkItem/_QfJAMJcWEei2nqqtDv7JZg?_action=com.ibm.team.workitem.impedimentWorkflow.action.startWorking

HttpMethod Used: HttpPut

Json Request: {"dc:identifier":"<observation ID>","rtc_cm:Status":{"rdf:resource=":"https:\/\/<domain name>\/ccm\/oslc\/workflows\/_w1ldJRkGEeWDiM8aLc-GlA\/states\/com.ibm.team.workitem.impedimentWorkflow/com.ibm.team.workitem.impedimentWorkflow.state.s3"}}

Note: For observations we have the below three states:

State: Invalid

<rtc_cm:Status rdf:resource="https://<domain name>/ccm/oslc/workflows/_w1ldJRkGEeWDiM8aLc-GlA/states/com.ibm.team.workitem.impedimentWorkflow/com.ibm.team.workitem.impedimentWorkflow.state.s3">

State: New

<rtc_cm:Status rdf:resource="https://<domain name>//ccm/oslc/workflows/_w1ldJRkGEeWDiM8aLc-GlA/states/com.ibm.team.workitem.impedimentWorkflow/com.ibm.team.workitem.impedimentWorkflow.state.s1">

State: Resolved

<rtc_cm:Status rdf:resource="https://<domain name>//ccm/oslc/workflows/_w1ldJRkGEeWDiM8aLc-GlA/states/com.ibm.team.workitem.impedimentWorkflow/com.ibm.team.workitem.impedimentWorkflow.state.s2">

The observation <observation ID> had the status as https://<domain name>//ccm/oslc/workflows/_w1ldJRkGEeWDiM8aLc-GlA/states/com.ibm.team.workitem.impedimentWorkflow/com.ibm.team.workitem.impedimentWorkflow.state.s1

Http Headers used:

              updateDefect.addHeader("Content-Type", "application/x-oslc-cm-change-request+json");

              updateDefect.addHeader("accept","text/json");

              updateDefect.addHeader("User-Agent", "MSIE 8.0");

Sample code:

StringEntity defrequest = new StringEntity(jsonRequest.toString());

updateDefect.setEntity(defrequest);

HttpResponse defectResponse = client.execute(updateDefect,context);

Output:

Http Response: 200

However the status of the observation still stays as https://<domain name>//ccm/oslc/workflows/_w1ldJRkGEeWDiM8aLc-GlA/states/com.ibm.team.workitem.impedimentWorkflow/com.ibm.team.workitem.impedimentWorkflow.state.s1