Withdraw of a petition?

[immihelp]

Hi Good afternoon,

I would like to stop an I-751 petition. Because of the circumstances I do not have a case number.
I was filling for my ex husband and I only have his A #. Can you let me know what the process is to stop this application?

Thank You

[immihelp]

You can write to USCIS to withdraw the petition.

If that does not work out, don't go to the interview.