18 October 2016
Go to My Account under your e filing log in. Click on View Form 15CA. It will show you all forms filed by you. The last column here is status where there I'll be option to withdraw form 15CA. After that you can re fill with correct data
18 October 2016
I am unsure of the process in such cases. Logic will dictate that you should write to the TDS Officer having jurisdiction over your TAN asking him to cancel or disregard the said Form 15CA. You can then file the fresh 15CA with correct details. I think that having an acknowledged copy of such communication should suffice. It may be a good idea to call TDS CPC or ASK and ask regarding whether there is an SOP for such cases.