There are a number of people on community.jenkins.io that are experienced with diagnosing those types of failures. They almost always need details that will help them as they try to help you resolve the issue. Some of the details that are needed include:
Detailed Jenkins, Java, and plugin versions
Provide the current Jenkins version, Java version, and the plugin names and versions that you’re using with that Jenkins version. There is a script that can be run in the Jenkins system console (“Manage Jenkins” >> “Script Console” ) to provide that information. That information is critical. Without it, they are limited to offering guesses based on your failure descriptions.
Detailed startup error messages
Provide the detailed error messages, especially from the Jenkins log file, including the stack traces that may be reported early in the startup process. This is less critical than the version information, but can make the diagnosis move much more quickly.
Detailed build failure error messages
Share one or more detailed error messages from build failures, including stack traces. This is less critical than the detailed error messages from startup, but can help identify later problems that the earlier steps might have missed.
Original Jenkins, Java, and plugin versions
Provide the original Jenkins version, Java version, and plugin versions that were working for you if you have them. Don’t worry too much if you don’t have all the details for this information. This is usually the least useful information, but may help others understand how large an upgrade you’ve performed. When upgrading across multiple years of releases and Java versions, there can be many different forms of surprises that were listed in the intervening changelogs and upgrade guides.