Seafile won't load locally but will remotely

Here's my setup: I have Ubuntu server 20.04, Apache2 and Seafile for a personal cloud. I followed the install guide from digitalriver and everything installed and did exactly what it was supposed to do. I have a FQD with a cert (using certbot) and that domain is forwarded to my modem via cloudns. My problem is this: I can load Seafile from a remote computer. I have port forwarding on my modem and (I think) a reverse proxy set up through Apache. On a remote computer I can type the domain and it loads Seafile. I can type the public IP for my modem and it loads the sample page from Apache. Locally if I type the server IP it loads the test page from Apache. But, I cannot access Seafile from any computer in my house. I've tried it with wireless connection and wired directly to the modem. I've tried using the domain and I've tried using the server IP with :8000 and :8082 (Seafile ports) and nothing will load. I assume this has something to do with DNS but I'm new to this so I really don't know where to look.

Any and all help appreciated, and please make it as simple as possible. Imagine you're telling a 5-year-old how to change an oil filter.

THANKS.