If you use Gmail - especially if you have an email program that pulls from Gmail - you may still have Gmail's multiple inboxes turned on and not even know it. This link will explain https://support.google.com/mail/answer/3055016?hl=en
We share this because quite often our emails end up in one of these other boxes that you may not even be aware you have.
To see what's in those boxes or to change your setting, you'll need to log into Gmail directly via the web.
If you're having trouble finding our response in your Gmail account, you can check the status of your request here.