Am I living in an illegal duplex

[Jesse Hayes]

Hello there. I am currently renting a property in the state of Colorado that is classified as a single family residential. I believe the proper permits and zoning was not done as this property is not a single family dwelling. The home is split down the middle, we share the same HVAC system and the same address. There are not two different entrances unless you count one front door and a garage door/side door. We also believe there is no fire walls to separate the "units". Does anyone have any insight as to whether or not this is legal, and if it is not, what should I do about this issue. Thank you in advance!