Calling cancel on job step waiting on input terminates normally, both curl POST or hubot http.post

Calling proceedEmpty fails with exception: input/ApproveDeployment/proceedEmpty.
jenkinsfile has:

timeout(time: 7, unit: 'DAYS'){
input id: 'ApproveDeployment', message: 'Waiting for response. Deploy to environment or cancel / abort'
}

Using curl POST or hubot POST both fail with the servlet exception.

Stack trace

javax.servlet.ServletException: java.lang.IndexOutOfBoundsException
at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:796)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:876
...

Even if data is added to the post it continues to fail.