I have been trying to start a SERO plan. If I enter the two zip codes I use for MN and SD, it says 'zip code not recognized', which seems to mean the offer may not be good in my areas...I think. When I enter 89101, Las Vegas, it works fine. So I continued with 89101, but it won't let me change the zip back to MN or SD and keep the SERO offer. It goes to a screen and again asks for a valid US zip code. If I get a Las Vegas # that is fine, but I would like/need to have it shipped/billed to me here, in either MN or SD. Thank you for any help! Sioux Falls, SD 57105, 57106, 57109, etc, none work.