Points earned by the referent is added but not subtract from the initial user gain

Hello, in the rule referralpoints the percentage of points earned by the referent is added but not subtract from the initial user gain.
For my system is not good because it is altered the real total gain, you can make this change?
If you think it's not right for everyone, would you be kind enough to show me how to do it, I need that.
Thank you.
Piero.

Hello, I tried to make the abovementioned amendment inserting in: components / com_altauserpoints / helper.php
after the line nr.237 this code

$db = &JFactory::getDBO();
$sql2 = "UPDATE ocuat_alpha_userpoints SET points = points - '$referraluserpoints' WHERE referreid = '$referrerid'";
$db->setQuery($sql2);
$db->query();

but no good because they take off their points to refferal user instead of referreid.
Where is the error?
Thanks in advance.

If you update the points like this, you'll loose it on next user sync.
You need to insert also a points activity in #__alpha_userpoints_details.

Sorry for the late reply but understand custom dev is not part of the support.