Team concert plugin with Jenkins Pipeline

I have the following installed:

-jenkins 2.19.1
-team concert plugin 1.2.0.1

I have created a pipeline, RTC finds it from the build definition, I have also checked that I can connect from Jenkins to RTC.

My script looks like this ( I used the groovy generator) ,

node {
    teamconcert([buildWorkspace: 'zCopyrights', value: 'buildWorkspace'])
}

I get this exception when I try and run it:
java.lang.NullPointerException
    at com.ibm.team.build.internal.hjplugin.RTCScm.checkout(RTCScm.java:1948)
    at org.jenkinsci.plugins.workflow.steps.scm.SCMStep.checkout(SCMStep.java:109)
    at org.jenkinsci.plugins.workflow.steps.scm.SCMStep$StepExecutionImpl.run(SCMStep.java:83)
    at org.jenkinsci.plugins.workflow.steps.scm.SCMStep$StepExecutionImpl.run(SCMStep.java:73)
    at org.jenkinsci.plugins.workflow.steps.AbstractSynchronousNonBlockingStepExecution$1$1.call(AbstractSynchronousNonBlockingStepExecution.java:52)
    at hudson.security.ACL.impersonate(ACL.java:221)
    at org.jenkinsci.plugins.workflow.steps.AbstractSynchronousNonBlockingStepExecution$1.run(AbstractSynchronousNonBlockingStepExecution.java:49)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

What have I missed?

Zoe