Application u/s 154 to CPC

Dear All,

I have recd intimation u/s 143(1). Some additions are made in the intimation. Now I want to make application u/s 154. It is mentioned in notes that if you seek rectification u/s 154 it is to be done with CPC.

However I am not able get any email id of CPC. I can not send the application by post  b,cause it has to send by simple post so without any delivery proof. So I may not have any proof of submission.

Can anybody guide on the issue? Thanks in advance.

Abhay