ag-grid aggregation for column which has row grouping to be true

I have a table as follows

As you can see in the picture,there is aggregation showing for Date of Issuance as child rows count + transactions.

Now, if I make Date of Issuance column to be rowGroup:true, grid is appearing as

Here the aggregation function which was written to get child rows count + transactions isn't working. Is there a way I can still show aggregation for a column which has rowGroup: true