c# - Saving Model is cascading update when I only want the main model updated -

i using c# web api , using repository standard save database. below shortened example using update database. use automapper flatten between user getuser region. when try update example username using updateuser model. use automapper map updateuser user. when try save gives me errors updating region. believe need region in user model because need automap between user getuser , region.

i not want update region. not understanding how move forward this. let me know if going ok , solution is.

public class user {     public int userid { get; set; }     public string username { get; set; }     public virtual region region { get; set; } }  public class getuser {     public int userid { get; set; }     public string username { get; set; }     public string region{get; set;} }  public class updateuser {     public int userid { get; set; }     public string username { get; set; }     public string regionid{get; set;} } 

from doing more research. found below automap ignore region in automap user has region pulled database. recommended way? below using automap:

 mapper.createmap<updateuser, user>().formember(x => x.region, opt => opt.ignore());