Currently running JcasC plugin 1.4 on jenkins openshift environment - Jenkins ver. 2.121.3

When I upgrade to any version of configuration-as-code the jenkins instance stops and fails to load after restart. I then have to downgrade it to 1.4 to start jenkins successfully. Any idea what to do here ?

SEVERE: Failed to initialize JenkinsSEVERE: Failed to initialize Jenkinshudson.util.HudsonFailedToLoad: org.jvnet.hudson.reactor.ReactorException: java.lang.Error: java.lang.reflect.InvocationTargetException at hudson.WebAppMain$3.run(WebAppMain.java:250)Caused by: org.jvnet.hudson.reactor.ReactorException: java.lang.Error: java.lang.reflect.InvocationTargetException at org.jvnet.hudson.reactor.Reactor.execute(Reactor.java:282) at jenkins.InitReactorRunner.run(InitReactorRunner.java:48) at jenkins.model.Jenkins.executeReactor(Jenkins.java:1102) at jenkins.model.Jenkins.<init>(Jenkins.java:904) at hudson.model.Hudson.<init>(Hudson.java:85) at hudson.model.Hudson.<init>(Hudson.java:81) at hudson.WebAppMain$3.run(WebAppMain.java:233)Caused by: java.lang.Error: java.lang.reflect.InvocationTargetException at hudson.init.TaskMethodFinder.invoke(TaskMethodFinder.java:110) at hudson.init.TaskMethodFinder$TaskImpl.run(TaskMethodFinder.java:175) at org.jvnet.hudson.reactor.Reactor.runTask(Reactor.java:296) at jenkins.model.Jenkins$5.runTask(Jenkins.java:1068) at org.jvnet.hudson.reactor.Reactor$2.run(Reactor.java:214) at org.jvnet.hudson.reactor.Reactor$Node.run(Reactor.java:117) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) at java.lang.Thread.run(Thread.java:748)Caused by: java.lang.reflect.InvocationTargetException at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at hudson.init.TaskMethodFinder.invoke(TaskMethodFinder.java:104) ... 8 moreCaused by: io.jenkins.plugins.casc.ConfiguratorException: No configurator for root element <credentials> at io.jenkins.plugins.casc.ConfigurationAsCode.invokeWith(ConfigurationAsCode.java:634) at io.jenkins.plugins.casc.ConfigurationAsCode.checkWith(ConfigurationAsCode.java:657) at io.jenkins.plugins.casc.ConfigurationAsCode.configureWith(ConfigurationAsCode.java:642) at io.jenkins.plugins.casc.ConfigurationAsCode.configureWith(ConfigurationAsCode.java:545) at io.jenkins.plugins.casc.ConfigurationAsCode.configure(ConfigurationAsCode.java:275) at io.jenkins.plugins.casc.ConfigurationAsCode.init(ConfigurationAsCode.java:267)