ATF steps not working

[hoathong99]

I am currently working with Yokohama version. Validate Variable Values  ATF step gives error like:

This step failed because the client error 'Invalid query string received:b4c92cf39341d210b5b3f4ed1dba1023: java lang NullPointerException:

Invalid query string received:87c65fa547e162103361b9fc416d43c9: java lang NullPointerException

Invalid query string received:14ce57d693b5d610ea62b91e1dba1086: java lang NullPointerException

Invalid query string received java lang NullPointerException: ' was detected on the page being tested. See failing Test Logs. To ignore these errors in the next test run, use 'Add all client errors to warning/ignored list' links.

My PDI in Zuric works fine.
I found a article about it https://support.servicenow.com/kb?id=kb_article_view&sysparm_article=KB2564290

PRB1889420 but couldn't open it 
Also whenever I try to add a validate feld state step, it just keep loading and freeze my instance then give me this error page. one window trying to add this step will freeze every other working SN window

Did anyone know and fixes or workaround?

[brianlan25]

There was a KB Article associated to the problem that contains a work around.

Step Variable Value Validation is failing with NPE and message w/ "Invalid query string received" - ...

If that doesn't work I would open a case with Now Support.

[hoathong99]

Can you please give me the workaround or fix mentioned in the kb?  both my company and personal account can't open the KB, I also asked my co-workers but they could'nt access the KB either

[hoathong99]

Can you please give me the workaround or fix mentioned in the kb?  both my company and personal account can't open the KB, I also asked my co-workers but they could'nt access the KB either