Why doesn't it allow to write down the props "Object field is not writable"?

Question

1C

Here is the code:
Request = New Request;
Request.Text = "
SELECT
| Incoming Goods of Services. Counterparty , | Incoming of Goods of Services . Date , | Incoming of Goods of Services . Link, | Incoming of Goods of Services . Goods. , | Amount, | VAT Amount, | Price, | GTD Number, | Country of Origin, | Account, | VAT Account, | Reflection VUSN, | Retail Price,
| AmountRetail,
| RateVATRetail,
| Contractor,
| AgreementContractor,
| AccountSettlements
| )
| FROM
| Document.Receipt of Goods/Services HOW Receipt of Goods
/Services |WHERE
| IncomingGoodsServices.Date >= &DateFrom
| AND Receipt of Goods/Services.Date <= &DateBY
| And Receipt of Goods/Services.Counterparty = &Counterparty1";
Query.SetParameter("DatePO", DatePO);
Query.SetParameter("DateS", DateS);
Query.SetParameter("Counterparty1", References.Counterparties.FindBy Name("companyLLC"));
QueryResult = Query.Execute();
While SelectionDetailedRecords.Next() Loop
Object = SelectionDetailedRecords.Reference.GetObject();
TabularSection Columns = SelectionDetailRecords.Reference.Products;
For Each Row from ColumnTabularPart Loop
Row.Price = Row.Price * 0.2;
EndCycle;
Object.Write();
EndCycle;
Platform 8.3 Thick Client

Answer 1

TabularSection Columns = SelectionDetailRecords.Reference.Products;

Products get from Object, not from SampleDetailedRecords
to name variable Object - not the best solution