Hi, there

I have just worked out the problem! There is the file 'ot_reward_points_display.php' lead to this problem.

$reward_ratio=GetGlobalRewardPointRatio();
$reward_points=$reward_points-($reward_ratio*$_SESSION['redeem_value']);

Now, all works ok for me after I commented out this block of code.

If you have the same trouble as me, you could try the method I offered.