This is because the standby is open read-only and cannot update any tables. When a user's account has to be locked on the standby database, it is locked only in memory there.
Query String Parse Error.
We have to forcefully relink FNDWRR.exe executable to make it work.
$ adrelink.sh force=y "fnd FNDWRR.exe"
If the above solution didn't work, you may refer the below Metalink Note.