IllegalMonitorStateException Error when adding subtutied users

Within JMIX 2.4.5 i am comming across this error java.lang.IllegalMonitorStateException: attempt to unlock read lock, not locked by current thread when attempting to add a substituted User to another. When going through the stacktrace it seems to be from SessionHolder.getActiveSessionsForUsernames(SessionHolder.java:93) Has anyone else come across this and can guide me with a fix?