@ jessicarash66
asked: "In my informed mail on the website shows that my check came yesterday but it still hasn't came in today. Where is my mail ."
By "informed mail on the website" are you saying it showed up at the post office, but it hasn't been delivered out to you yet? i.e., is "the website" you are referring to the USPS Informed Delivery option--is that what you mean? Or did you mean something else?
If it showed up in the USPS Informed Delivery feature, i.e., if the USPS has possession of it, but hasn't yet delivered it, you'd have to inquire with your post office branch as to what happened to it, or when it will be delivered out.