I have done the resolution and still have the same issue

[Mustafa Abusalah]

This question is in reference to Atlassian Documentation: User directory synchronization fails with NullPointerException at HibernateConfluenceUserDao.rename

Ask your question here...

[Nic Brough -Adaptavist-]

What, exactly, does the log say now?  What is the output from the SQL query?

[Mustafa Abusalah]

The query returned zero records. The log returnes the same error 

[Nic Brough -Adaptavist-]

Ok, this needs to go to Atlassian support really - you've done everything right and it's a bug in their stuff.

[Mustafa Abusalah]

This is exactly what I've done. Thank you

[Avinash Singh]

The resolution says to run the sql query 

SELECT * FROM user_mapping WHERE LOWER(username) != lower_username OR lower_username IS NULL;

and Fix the mismatch accordingly, and the issue should be resolved.  What does this mean? How do you fix the mismatch? The entries cannot just be deleted as there are other tables referencing it.

[Nic Brough -Adaptavist-]

Have you followed the rest of the instructions?

[Avinash Singh]

sorry but where is the rest of the instructions all I see is this 

https://confluence.atlassian.com/confkb/user-directory-synchronization-fails-with-nullpointerexception-at-hibernateconfluenceuserdao-rename-794500074.html

[Nic Brough -Adaptavist-]

You need to update the lines the SQL finds and make them the same.