[#14651] - External user throws j_spring_security_check error

This error is for Jasperserver CE v8.2.0.
I modified my LDAP file based on this sample-applicationContext-externalAuth-LDAP.xml(jasperreports-server-cp-8.2.0-bin\samples\externalAuth-sample-config). However, when I input blank or incorrect passwords of external users it shows that j_spring_security_check error. For internal users like jasperadmin, they work as normal. I don't know what is wrong with this version.
My previous LDAP file was working fine with Jasperserver CE v8.1.1. After the modification for the new update of LDAP to support "externalUserLoginEventService", it shows an error only for external users. If anyone knows how to fix this, please help share your solution. Thank you.