SQL Server Cannot open database requested by the login

Question

I'm making a login/register SQL Server system and when i made a string to connect i have this problem. My database name is Vartotojai here is the code

    public static DataTable ExecSP(string spname, List<SqlParameter> sqlParams = null)
    {
        string strConnect = "Server=DESKTOP-MR4OJCU\\MSSQLSERVER01;Database=Vartotojai;Trusted_Connection=True";

        SqlConnection conn = new SqlConnection();

        DataTable dt = new DataTable();

        try
        {
            //Connect to the DT.
            conn = new SqlConnection(strConnect);
            conn.Open();

            //Build an sql command / query 
            SqlCommand cmd = new SqlCommand(spname);
            cmd.CommandType = CommandType.StoredProcedure;
            cmd.Parameters.AddRange(sqlParams.ToArray());


            //Execute
            SqlCommand command = conn.CreateCommand();
            SqlDataReader dr = cmd.ExecuteReader();

            //fill dt with results
            dt.Load(dr);



        }
        catch (Exception ex)
        {

            throw ex;
        }
        finally
        {
            //ner skirtumo kas pasaidare isijungs
            conn.Close();



        }
        return dt;
    }

}

}

System.Data.SqlClient.SqlException: 'Cannot open database "Vartotojai" requested by the login. The login failed.
Login failed for user 'DESKTOP-MR4OJCU\interkodas'.'