Entity Framework / LINQ error: column prefix "Project1" does not match table name or alias used in query

I have the following LINQ query:

var queryEvents = (from p in db.cl_contact_event
                   where p.time_of_contact >= beginDate && p.time_of_contact < endDate
                   group p by p.contact_list_name into g
                   select new PenRawModel
                   {
                        listName           = g.Key,
                        download           = g.Max(a => a.total_number_of_records),
                        dials              = g.Where(a => a.ov_dial_start_time != null).Count(), //This fails.
                        //dials              = g.Sum(a => a.ov_dial_start_time != null ? 1 : 0), //This works.
                        agentConnects      = g.Sum(a => a.ov_trunk_released_time != null ? 1 : 0),
                        abandons           = g.Sum(a => a.response_status == "DAC" || a.response_status == "DAD" ? 1 : 0),
                        rightPartyContacts = g.Sum(a => a.response_status == "PTP" || a.response_status == "RPC" ? 1 : 0),
                        promiseToPays      = g.Sum(a => a.response_status == "PTP" ? 1 : 0),
                        talkTime           = g.Sum(a => EntityFunctions.DiffSeconds(a.ov_call_connected_time, a.ov_trunk_released_time)) ?? 0,
                        wrapTime           = g.Sum(a => EntityFunctions.DiffSeconds(a.ov_trunk_released_time, a.record_released_time)) ?? 0
                   }

On startup, it gives me an error:

"The column prefix 'Project1' does not match the table name or the alias name used in the query. Either the table is not specified in FROM or has a correlation name that should be used instead."

The reason for the refusal is:

dials = g.Where(a => a.ov_dial_start_time != null).Count(),

If I replace this line of code with the comment below, then the query works just fine. I would rather use .Where / .Count, because it's easier for someone to decrypt and understand the intent of the code.

Can someone help me make it clear why this fails and how can I fix it?

- SQL, Sybase :

SELECT 
1 AS [C1], 
[Project2].[contact_list_name] AS [contact_list_name], 
[Project2].[C1] AS [C2], 
[Project2].[C10] AS [C3], 
[Project2].[C2] AS [C4], 
[Project2].[C3] AS [C5], 
[Project2].[C4] AS [C6], 
[Project2].[C5] AS [C7], 
CASE WHEN ([Project2].[C6] IS NULL) THEN 0 ELSE [Project2].[C7] END AS [C8], 
CASE WHEN ([Project2].[C8] IS NULL) THEN 0 ELSE [Project2].[C9] END AS [C9]
FROM ( SELECT 
    [Project1].[C1] AS [C1], 
    [Project1].[C2] AS [C2], 
    [Project1].[C3] AS [C3], 
    [Project1].[C4] AS [C4], 
    [Project1].[C5] AS [C5], 
    [Project1].[C6] AS [C6], 
    [Project1].[C7] AS [C7], 
    [Project1].[C8] AS [C8], 
    [Project1].[C9] AS [C9], 
    [Project1].[contact_list_name] AS [contact_list_name], 
    (SELECT 
        Count([Filter2].[A1]) AS [A1]
        FROM ( SELECT 
            1 AS [A1]
            FROM [mel].[cl_contact_event] AS [Extent2]
            WHERE ((([Extent2].[time_of_contact] >= @p__linq__0) AND ([Extent2].[time_of_contact] < @p__linq__1)) AND (([Project1].[contact_list_name] = [Extent2].[contact_list_name]) OR (([Project1].[contact_list_name] IS NULL) AND ([Extent2].[contact_list_name] IS NULL)))) AND ([Extent2].[ov_dial_start_time] IS NOT NULL)
        )  AS [Filter2]) AS [C10]
    FROM ( SELECT 
        [GroupBy1].[A1] AS [C1], 
        [GroupBy1].[A2] AS [C2], 
        [GroupBy1].[A3] AS [C3], 
        [GroupBy1].[A4] AS [C4], 
        [GroupBy1].[A5] AS [C5], 
        [GroupBy1].[A6] AS [C6], 
        [GroupBy1].[A7] AS [C7], 
        [GroupBy1].[A8] AS [C8], 
        [GroupBy1].[A9] AS [C9], 
        [GroupBy1].[K1] AS [contact_list_name]
        FROM ( SELECT 
            [Filter1].[K1] AS [K1], 
            Max([Filter1].[A1]) AS [A1], 
            Sum([Filter1].[A2]) AS [A2], 
            Sum([Filter1].[A3]) AS [A3], 
            Sum([Filter1].[A4]) AS [A4], 
            Sum([Filter1].[A5]) AS [A5], 
            Sum([Filter1].[A6]) AS [A6], 
            Sum([Filter1].[A7]) AS [A7], 
            Sum([Filter1].[A8]) AS [A8], 
            Sum([Filter1].[A9]) AS [A9]
            FROM ( SELECT 
                [Extent1].[contact_list_name] AS [K1], 
                [Extent1].[total_number_of_records] AS [A1], 
                CASE WHEN ([Extent1].[ov_trunk_released_time] IS NOT NULL) THEN 1 ELSE 0 END AS [A2], 
                CASE WHEN ((N'DAC' = [Extent1].[response_status]) OR (N'DAD' = [Extent1].[response_status])) THEN 1 ELSE 0 END AS [A3], 
                CASE WHEN ((N'PTP' = [Extent1].[response_status]) OR (N'RPC' = [Extent1].[response_status])) THEN 1 ELSE 0 END AS [A4], 
                CASE WHEN (N'PTP' = [Extent1].[response_status]) THEN 1 ELSE 0 END AS [A5], 
                DATEDIFF (second, [Extent1].[ov_call_connected_time], [Extent1].[ov_trunk_released_time]) AS [A6], 
                DATEDIFF (second, [Extent1].[ov_call_connected_time], [Extent1].[ov_trunk_released_time]) AS [A7], 
                DATEDIFF (second, [Extent1].[ov_trunk_released_time], [Extent1].[record_released_time]) AS [A8], 
                DATEDIFF (second, [Extent1].[ov_trunk_released_time], [Extent1].[record_released_time]) AS [A9]
                FROM [mel].[cl_contact_event] AS [Extent1]
                WHERE ([Extent1].[time_of_contact] >= @p__linq__0) AND ([Extent1].[time_of_contact] < @p__linq__1)
            )  AS [Filter1]
            GROUP BY [K1]
        )  AS [GroupBy1]
    )  AS [Project1]
)  AS [Project2]