Having trouble with Microsoft Outlook 2013?

So, I’ve got two different email accounts set up here in Microsoft Outlook 2013.
The automatic reply feature used to work perfectly fine by filtering responses so that anyone from my own domain wouldn't get an auto-reply, while everyone else outside the organization would.
In the settings, there's clearly an option to toggle replies for people inside versus outside the organization, and it worked flawlessly before, but now for some reason, it won't let me separate them; if I turn on the out-of-office reply for external contacts, my internal colleagues end up getting the response too.
Since these accounts are essentially merged into the same inbox, how am I supposed to configure this so that only the outsiders receive the reply?

Thanks for bearing with me, because honestly, half the time I can't even make sense of my own thoughts.

Check if you accidentally left something active for the inside folder.
Maybe there's an old rule hanging around somewhere.
It’s right next to where the Inside and Outside tabs are.
Try nuking any rules tied to automatic replies, then just double-check that you actually have the right mailbox selected to begin with.

So you’ve got two different email accounts set up in Outlook, right? But here's the kicker—how many actual mail servers are we talking about? Like, how many different domains is each one actually responsible for?