Error the function evaluation require all threads to run in WPF C#?

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C#

SQL-Server

WPF

SQL-Server-2014

, +

I'm Using WPF C# and Entity Framework i did execute this query in SQL Server :

SELECT * FROM STUF_DEF
Full JOIN TCOD_VAHEDS ON STUF_DEF.VAHED = TCOD_VAHEDS.CODE

so when i want to show data in DataGrid , i see thats empty

i check this line , i see this proublem

This is my code behind in cs :

var qre = dbms.Database.SqlQuery<STUF_DEF>("SELECT * FROM STUF_DEF Full JOIN TCOD_VAHEDS ON STUF_DEF.VAHED = TCOD_VAHEDS.CODE");
            dgv_Kalaha.ItemsSource = qre.ToList();

ther is no value in qre because :

**

Error The function evaluation requires all threads to run.

Please help me

What I have tried:

c# - Error: The function evaluation requires all threads to run - Stack Overflow[^]