Dapper.net 2.0 Unable to cast exception

The exception that am recieving is clear. i did use dapper before and it worked great but now am having hard time.

Unable to cast object of type 'System.Func2[System.Data.IDataReader,WebApplication1.Modal.Users]' to type 'System.Func2[System.Data.IDataReader,System.Object]'.

User Class is

public class Users : MainSharedTable
    {

        public int FkReceiverID { get; set; }
        public string Password { get; set; }

    }

MainSharedTable is

public class MainSharedTable 
    {
        public int ID { get; set; }
        public bool Active { get; set; }
    }

and the exception happens here

public   IEnumerable<Users> GetAll()
    {

            var conn = GetOpenConnection();
           var data = conn.Query<Users>("SELECT * FROM arabaicsms.users  "); // error happens here 
            ConnectionClose();

        return data;
    }

any help is appreciated note: my db is MYSQL and if do not cast the returned object i receive a dictionary

full stack

[InvalidCastException: Unable to cast object of type 'System.Func`2[System.Data.IDataReader,WebApplication1.Modal.Users]' to type 'System.Func`2[System.Data.IDataReader,System.Object]'.]
   Dapper.SqlMapper.GetTypeDeserializerImpl(Type type, IDataReader reader, Int32 startBound, Int32 length, Boolean returnNullIfFirstMissing) +10454
   Dapper.TypeDeserializerCache.GetReader(IDataReader reader, Int32 startBound, Int32 length, Boolean returnNullIfFirstMissing) +412
   Dapper.TypeDeserializerCache.GetReader(Type type, IDataReader reader, Int32 startBound, Int32 length, Boolean returnNullIfFirstMissing) +379
   Dapper.SqlMapper.GetTypeDeserializer(Type type, IDataReader reader, Int32 startBound, Int32 length, Boolean returnNullIfFirstMissing) +72
   Dapper.SqlMapper.GetDeserializer(Type type, IDataReader reader, Int32 startBound, Int32 length, Boolean returnNullIfFirstMissing) +520
   Dapper.<QueryImpl>d__58`1.MoveNext() +1293
   System.Collections.Generic.List`1..ctor(IEnumerable`1 collection) +387
   System.Linq.Enumerable.ToList(IEnumerable`1 source) +119
   Dapper.SqlMapper.Query(IDbConnection cnn, String sql, Object param, IDbTransaction transaction, Boolean buffered, Nullable`1 commandTimeout, Nullable`1 commandType) +787
   WebApplication1.BL.UsersBs.GetAll() in C:\Users\pc\documents\visual studio 2015\Projects\ArabaicSmsWeb\WebApplication1\BL\UsersBs.cs:25
   WebApplication1.login.Page_Load(Object sender, EventArgs e) in C:\Users\pc\documents\visual studio 2015\Projects\ArabaicSmsWeb\WebApplication1\login.aspx.cs:17
   System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e) +51
   System.Web.UI.Control.OnLoad(EventArgs e) +95
   System.Web.UI.Control.LoadRecursive() +59
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +780

the table at the database is like below

there is nothing strange around, i did even capitalize the table latter and make them small also but the same error is there