subgrid - only 1 row shown

I have converted an existing grid to use subgrids. Even though the subgrid contains multiple rows when I click the expand icon on the grid only one row (the header row) of the subgrid is shown. Shouldn’t the entire subgrid be shown regardless of the number of rows? Is there some setting that tells the grid to display multiple rows for the subgrid?

Please provide us example where we can reproduce this issue (Please send such example directly to the support@dhtmlx.com)