Can't place order after migration data from Magento 1 to Magento 2

Question

When I try place order, it show "Please choose a valid discount amount."

Answer 1

Section responsible for that error looks like

        // Check if discount amount not negative
        if ($this->hasDiscountAmount()) {
            if ((int)$this->getDiscountAmount() < 0) {
                throw new \Magento\Framework\Exception\LocalizedException(__('Please choose a valid discount amount.'));
            }
        }

Check your cart rules after migration cause this error is thrown when applied discount amount is less than 0.