Hi Prasant and Abhi
Thanks for your help, now the LDAP verification can work.
I traced the code and found that the root cause is because of the LDAP Group parameter setting. We must configure the parameter "LDAP_END_USER_AUTH_SUFFIX" and set the value empty.
If you don't configure "LDAP_END_USER_AUTH_SUFFIX", the program will automatically bind user with "@+LDAP IP" and use the new user ID to try to login LDAP server.
Best regards
James