Add row to existing Dataframe C#

Question

I'm currently trying to add a row with specific values.
My code is this:

StringDataFrameColumn article_nr_column = new StringDataFrameColumn("Article Nr");
StringDataFrameColumn brand_column = new StringDataFrameColumn("Brand");
StringDataFrameColumn article_group_column = new StringDataFrameColumn("Article Group");
PrimitiveDataFrameColumn<DateTime> date_column = new PrimitiveDataFrameColumn<DateTime>("Date");
PrimitiveDataFrameColumn<DateTime> date_of_stock_column = new PrimitiveDataFrameColumn<DateTime>("Date of Stock");
PrimitiveDataFrameColumn<int> stock_column = new PrimitiveDataFrameColumn<int>("Stock");
PrimitiveDataFrameColumn<int> stock_Limit_min_column = new PrimitiveDataFrameColumn<int>("Stock Limit min");
PrimitiveDataFrameColumn<int> stock_Limit_max_column = new PrimitiveDataFrameColumn<int>("Stock Limit max");
PrimitiveDataFrameColumn<int> open_Orders_column = new PrimitiveDataFrameColumn<int>("open Orders");
PrimitiveDataFrameColumn<int> reservations_column = new PrimitiveDataFrameColumn<int>("Reservations");
PrimitiveDataFrameColumn<int> delivery_days_column = new PrimitiveDataFrameColumn<int>("Estimated delivery time in days");
PrimitiveDataFrameColumn<double> sales_column = new PrimitiveDataFrameColumn<double>("Sales");
StringDataFrameColumn email_column = new StringDataFrameColumn("EMail");
StringDataFrameColumn tecid_column = new StringDataFrameColumn("TecID");

//declare values with datatype of equivalent column
string tecid= "test";
....

DataFrame df_to_forecast = new DataFrame(tecid_column, email_column, article_nr_column, date_column, sales_column, brand_column, article_group_column, stock_column, date_of_stock_column, reservations_column, open_Orders_column, stock_Limit_min_column, stock_Limit_max_column, delivery_days_column);

//Now I try to add the values to the dataframe
df_to_forecast.Append(tecid, ...);

I'm getting the error: No overload for method 'Append' takes 13 arguments
I know that I have to put all the values in a Row, but how can I do this?

I know I could Append the value to the Columns itself but I don't what to do it this way