Tolerance key PP - Lower limit

We have configured tolerance key PP with lower limit of 0$ for both absolute and percentage. When I try to post the invoice with a lower price, I receive a warning message that the price is too low (which is correct).

The problem is that when I try to post this invoice, it is getting posted without being blocked. Since the lower limit is defined, shouldn't the invoice be blocked when it is below lower limit defined.

Is there any other setting that I need to make to ensure that the invoice is getting blocked when it is posted below the lower limit defined? Please help. Thanks.