Why does the E2362 Cannot access protected symbol TControl.Text appear?

Here is the code that causes the error:

procedure TfrmQuoteTemp.showData;
 begin
  lblFirstName.Text := query.FieldByName('First Name').AsString;
  lblLastName.Text := query.FieldByName('Last Name').AsString;
  lblAddress.Text := query.FieldByName('Address').AsString;
  lblTown.Text := query.FieldByName('Town').AsString;
  lblCounty.Text := query.FieldByName('County').AsString;
  lblPostcode.Text := query.FieldByName('Postcode').AsString;
  lblTelNo.Text := query.FieldByName('TelNo').AsString;
 end;

This error happens only with Tlabel and I cannot change their Text property at all.