Datatable - not showing dynamic row from HTTP response

Hi,

I have a datatable where initially i display 2 row and after a button click my hhtp service fetch 5 row and then it display error "Error unexpected attribute "group"(schema: oxf:/ops/xforms/xforms-server-response.rng)"

If the number of row at 2nd time is less than or equal to initial time then it work fine otherwise it give error .

Is this is related to re-initialize the datatable or something else ??

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Thanks,
Saket