err = conn.Bind(bindDN, password)
	if err != nil {
		errRet := fmt.Errorf("LDAP auth failed for DN %s: %w", bindDN, err)
		return "", nil, errRet
	}

	// Bind to the lookup user account again to perform group search.
	if err = l.LDAP.LookupBind(conn); err != nil {
		return "", nil, err
	}

	// User groups lookup.
	groups, err := l.LDAP.SearchForUserGroups(conn, username, bindDN)
	if err != nil {
		return "", nil, err