All three are the same application. What changes is how many people get in, how many documents you issue per year and which advanced modules you have: Emprendedor goes up to 500 documents a year, Empresario makes them unlimited with up to ten users, and Enterprise removes every cap.
And if none of this was your case?
If you are already a customer, write from inside the app: it arrives with your company attached and gets solved sooner. If you are not one yet, or you want to talk about a migration, about pricing or to the press, that is what the contact form is for.