Windows Server 2016 - VPN clients can't talk to server on normal IP address

Hello everyone! I have Server 2016 setup to do VPN. I used to run it as SSTP but switched over to L2TP because of security issues with Macs.

Anyway up until a few weeks ago, the server would give out addresses to VPN clients via DHCP and those clients could talk to the server (file sharing) on it's normal network address. They could access this address either locally or via VPN with no issues.

A few weeks ago, all of a sudden, the server started getting a secondary address from DHCP for the "internal" adapter in the RRAS console. So, local clients can still talk to the server on it's normal IP address (only one NIC). But, when VPN clients come in, they can't communicate to the standard IP address. Any mapped shares show up empty or error out, can't ping the address, nothing. But, they can access the server via the secondary address that gets listed for the "internal" adapter in RRAS when a client connects. I have this sortuv controlled as a work around right now by setting up an address range for the RRAS to hand out to VPN clients. The secondary server address (the one we don't want to use) is the first address from that static pool. It seems that this started after I did maintenance and windows updates. Is this a "feature"? How do I stop it from doing this? I'd rather the server answer VPN clients on it's normal IP address just like it has for the last 3 years without issue. I'm not sure how to get it to not use the "new" address for VPN clients. Right now, I have a work around that the users are mapping a second drive to the "new" IP address so they can access files while on the VPN. That's pretty much all this server is used for.

Thanks! =)