SQL Query in SSMS works but not in C#

Question

I have this query which returns an image stored in an MS SQL database. If I run this in SSMS (SQL Management Studio) it works perfectly and returns instantly.

select image from extra where product_id = 184

However in .NET Core MVC it doesn't return, and the SQL command simply times out and an error 500 occurs stating the SQL Command timeout. I have even gave it 10 full minutes to "return" the SQL command and it still doesn't.

[HttpGet("{id}/image")]
public object Get(int id)
{
    using (SqlConnection connection = new SqlConnection(connectionstring)) {
        using (SqlCommand sqlCommand = new SqlCommand("select top 1 image from extra where product_id = @product_id", connection))
        {
            sqlCommand.Parameters.AddWithValue("@product_id", id);
            sqlCommand.Connection.Open();
            using (SqlDataReader sqlDataReader = sqlCommand.ExecuteReader())
            {
                object img = null;

                if (sqlDataReader.HasRows)
                {
                    sqlDataReader.Read();
                    img = new
                    {
                        image = sqlDataReader["image"] == DBNull.Value ? null : "data:image/png;base64," + Convert.ToBase64String((byte[])sqlDataReader["image"])
                    };

                    return img;
                }
            }
        }
    }

    return new { error = true, message = "Unknown error in image getting" };
}

Stepping through the code in debug mode. It doesn't get past this line:

SqlDataReader sqlDataReader = sqlCommand.ExecuteReader();

This pastebin is what the SQL query returns if I run it in SSMS.

EDIT: SQL Version is Microsoft SQL Server 2017 (RTM-CU15-GDR) (KB4505225) - 14.0.3192.2 (X64) Jun 15 2019 00:45:05 Copyright (C) 2017 Microsoft Corporation Standard Edition (64-bit) on Windows Server 2012 R2 Standard 6.3 <X64> (Build 9600: ) (Hypervisor)

Answer 1

Please try below.

Also put a break point on the Catch, and see what ex.Message is

try
            {
                SqlCommand sqlCommand = new SqlCommand("select top 1 image from extra where product_id = @product_id", connection);
                sqlCommand.Parameters.Add(new SqlParameter("@product_id", id));
                using (SqlDataReader sqlDataReader = sqlCommand.ExecuteReader())
                {
                    while (sqlDataReader.Read())
                    {
                        img = new
                        {
                            image = sqlDataReader["image"] == DBNull.Value ? null : "data:image/png;base64," + Convert.ToBase64String((byte[])sqlDataReader["image"])
                        };
                        connection.Close();
                        return img;
                    }
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
            }

            return new { error = true, message = "Unknown error in image getting" };