Sending mail via one account, but recipient responds to another

Hello,

I recently removed a gmail account from my mail application, but I am having an issue where I send an email via my regular (dnielle.dXXXXX@gmail.com) account, but the recipient is responding to the account (westcaXXXXX@gmail.com) that I have removed from the application. I have no idea where to fix this issue because in my mail preferences, the (westcaXXXXX@gmail.com) account does not show up.

Help would be much appreciated! Thanks!