How to Use E-COA?  

Before getting started with this new tool, you need to create a USCIS online account. You will also need to have your new physical and mailing addresses, old address and information about any pending application, petition, or request, such as the receipt number, to facilitate the process.

Important to Note:

Changing your address with the U.S. Postal Service (USPS) does not automatically update your address with USCIS