unable to run builds via nodes after updating jenkins to latest version. all nodes are connected and on idle. 

Nodes status:

<===[JENKINS REMOTING CAPACITY]===>channel started Remoting version: 3.35 This is a Unix agent Evacuated stdout Agent successfully connected and online Sep 16, 2019 9:05:20 AM org.jenkinsci.remoting.util.AnonymousClassWarnings warn WARNING: Attempt to (de-)serialize anonymous class net.bull.javamelody.RemoteCallHelper$1; see:

https://jenkins.io/redirect/serialization-of-anonymous-classes/

Build error:

FATAL: Jenkins.instance is missing. Read the documentation of Jenkins.getInstanceOrNull to see what you are doing wrong.
Also: hudson.remoting.Channel$CallSiteStackTrace: Remote call to QA1Web
at hudson.remoting.Channel.attachCallSiteStackTrace(Channel.java:1741)
at hudson.remoting.UserRequest$ExceptionResponse.retrieve(UserRequest.java:356)
at hudson.remoting.Channel.call(Channel.java:955)
at hudson.FilePath.act(FilePath.java:1071)
at hudson.FilePath.act(FilePath.java:1060)
at hudson.scm.SubversionSCM.checkout(SubversionSCM.java:901)
at hudson.scm.SubversionSCM.checkout(SubversionSCM.java:837)
at hudson.scm.SCM.checkout(SCM.java:504)
at hudson.model.AbstractProject.checkout(AbstractProject.java:1206)
at hudson.model.AbstractBuild$AbstractBuildExecution.defaultCheckout(AbstractBuild.java:574)
at jenkins.scm.SCMCheckoutStrategy.checkout(SCMCheckoutStrategy.java:86)
at hudson.model.AbstractBuild$AbstractBuildExecution.run(AbstractBuild.java:499)
at hudson.model.Run.execute(Run.java:1815)
at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:43)
at hudson.model.ResourceController.execute(ResourceController.java:97)
at hudson.model.Executor.run(Executor.java:429)
java.lang.IllegalStateException: Jenkins.instance is missing. Read the documentation of Jenkins.getInstanceOrNull to see what you are doing wrong.
at jenkins.model.Jenkins.get(Jenkins.java:772)
at hudson.model.Hudson.getInstance(Hudson.java:77)
at hudson.scm.SubversionWorkspaceSelector.syncWorkspaceFormatFromMaster(SubversionWorkspaceSelector.java:105)
at hudson.scm.SvnClientManager.<init>(SvnClientManager.java:31)
at hudson.scm.SubversionSCM.createClientManager(SubversionSCM.java:1045)
at hudson.scm.SubversionSCM$CheckOutTask.invoke(SubversionSCM.java:972)
at hudson.scm.SubversionSCM$CheckOutTask.invoke(SubversionSCM.java:952)
at hudson.FilePath$FileCallableWrapper.call(FilePath.java:3051)
at hudson.remoting.UserRequest.perform(UserRequest.java:211)
at hudson.remoting.UserRequest.perform(UserRequest.java:54)
at hudson.remoting.Request$2.run(Request.java:369)
at hudson.remoting.InterceptingExecutorService$1.call(InterceptingExecutorService.java:72)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
SSH: Current build result is [FAILURE], not going to run.