add new discount/coupon does not add a new rule

Before: I was able to add a new discount/coupon combination, and this automatically created a discount rule responding to event: Calculating the sell price of a product (no idea if this comes from discounts or coupons). This meant that the coupon was usable right away. However, now, when I add a new discount/coupon, this rule is not created. If I attach the coupon to an older discount it works, But the new discount does not work unless I manually create a rule for it.

this might seem of topic, but it believe it could be relevant: I recently had a similar problem with the flat_rate/shipping modules. When I add a new flat rate service: before adding a new flat rate service will create a component. Now, when I add the service I have to create this component myselft (I wonder if for some reason modules which create rules or components are prevented from doing so)

Any help will be appreciated.