Hi Vikrant,
Thanks for you quick response.
But the issue is with step-1 you described in your mail.
I am able to change the status of 1001 from completed to ready to cancel but from ready to cancel i am not able to change it to cancel. system gives an error.
because of thisl i am not able to cancel the 1001 task, i can not post new transactions by coping it.1001 is active for same transaction number.
Please check in your system and advice as this is related to authorization or it is standard.