c# - ASP.NET MVC5: The ObjectContext instance has been disposed -

i use asp.net mvc5 ef, in few string received "the objectcontext instance has been disposed , can no longer used operations require connection". what's wrong?

public jsonresult getresponibleparty() {     list<ci_responsibleparty> resparty;     using (metabasedbcontext context = new metabasedbcontext())     {         resparty = context.setofresponsibleparty.tolist();         return json(resparty, jsonrequestbehavior.allowget);     }        } 

move return statement after using block. have created list , held in variable.

public jsonresult getresponibleparty() {     list<ci_responsibleparty> resparty;     using (metabasedbcontext context = new metabasedbcontext())     {         resparty = context.setofresponsibleparty.tolist();     }            return json(resparty, jsonrequestbehavior.allowget); }