I am also experiencing this, but it is inconsistent.
Sometimes I do receive the NullPointerException
Sometimes a job fails and there is no indication in the logs that anything failed to occur, but a Jira ticket is not created.
Sometimes tickets are created as expected.
This inconsistent behaviour occurs on projects that have been copied from one another, with no apparent difference in configuration.
I am presently tweaking issue type and severity values to see if I can get consistent behaviour but have not found a magic combination yet.
I am using Jenkins 2.176.1, Jira Plugin 3.0.8, and I am trying to integrate with a hosted Jira Cloud site.