Oracle Alert generating 2 emails

Hi Guys

  I have created an alert on the App: Order Management, Table:OE_ORDER_HEADERS_ALL (After Insert & After Update) with the following query. this is suppose to generate one alert. but the same is generating 2 alert emails. kindly help me out

select order_number into &orde_number

from OE_ORDER_HEADERS_ALL

where order_type_id=1017

and attribute10='Y'

and booked_flag='N'

AND order_number IN (Select order_number from OE_ORDER_HEADERS_ALL where rowid=:rowid)

Note: if this is not the correct forum for alerts issues. then kindly direct to the same

Regards

Arfeen Khan