Thanks for your time @babylon1999 !
I understand that they are not bugs, but they are a major problem in the client flow and we are still blind. So far I have not found any solution to know all the notifications (alerts/errors) that appear to potential customers. I need to know if, for example, customers write the coupon wrong (which can help me modify the name of the coupon) or if the coupon has reached its maximum number of uses and I am not aware of it. Knowing those notifications help us to react in time!