Error when running JQL of 'assignee was not in (EMPTY)'

Summary

According to Advanced searching, assignee field should support operation of 'WAS NOT IN' .
However, when using EMPTY together, a strange error ( Error occurred communicating with the server. Please reload the page and try againIssue ) occurs.

This ticket is related to below bug:

• JSDSERVER-6675: Adding invalid JQL in new JSD queue will cause the Queue screen to show as Empty (fixed in Jira Service Management Server and Data Center 4.7.0)

– Added Aug24,2023 –
This problem does not happen in cloud environment , so it should not a syntax problem.

This is reproducible on Data Center: (yes)

Steps to Reproduce

1. Search for issues
2. Advanced mode
3. Running below JQL

   assignee was not in (EMPTY)
   

Expected Results

No error happen

Actual Results

It shows an error of "Error occurred communicating with the server. Please reload the page and try again" in UI.

Also, below errors can be found in application log

2023-08-17 07:20:26,837+0000 http-nio-8080-exec-3 url: /rest/issueNav/1/issueTable; user: rli ERROR rli 440x1042x2 17vmyku 172.17.0.1 /rest/issueNav/1/issueTable [c.a.p.r.c.error.jersey.ThrowableExceptionMapper] Uncaught exception thrown by REST service: name should not be null!
com.atlassian.jira.util.dbc.Assertions$NullArgumentException: name should not be null!
	at com.atlassian.jira.util.dbc.Assertions.notNull(Assertions.java:25)
	at com.atlassian.jira.jql.resolver.UserResolverImpl.getIdsFromName(UserResolverImpl.java:46)

Workaround

Currently there is no known workaround for this behavior.