Are you sure you’ve added the constant definition in the right place? As the BuddyPress codex says:
When adding the code to wp-config.php, place it after define(‘DB_COLLATE’, ”); and before the authentication keys. If you add this line to the bottom of wp-config.php, it will not work.
The groups_unban_member hook fires before the unbanning of a member from a group and the the groups_ban_member hook fires before the banning of a member from a group.
Both hooks are defined in the bp-groups/bp-groups-functions.php file.
add_filter( 'bp_members_signup_error_message', 'function_voornaam', 10, 2 );
function function_voornaam( $value, $fieldname ) {
if ( $fieldname == 'field_1' ) {
return '<style>{font-family:bold}</style> you have to enter name.';
}
return $value;
}