SP2-0642: SQL*Plus internal error state 2131, context 0:0:0. Unsafe to proceed

There was an issue today, A DBA from our team has installed four databases in same oracle home.
For one of the Database, everything was working normal.
For rest 3 DBA was getting this error while running any sql command..

SP2-0642: SQL*Plus internal error state 2131, context 0:0:0. Unsafe to proceed

Oracle suggested to relink the Oracle executables and We checked the sudo bit on oracle executable also.

Then,

I compared the spfile for all four instances and found.

The working Database had NLS_DATE_FORMAT =
And Non working Databases were having NLS_DATE_FORMAT='DD-MM-YYYY'

As the date format was different and after unsetting DD-MM-YYYY , all Databases worked fine.


Now , I have a question , That all DB under one oracle home must have the same NLS_DATE_FORMAT  ? OR same NLS_Parameters.

I will try to find more on this.