Ring Pro Wired and Nicor Prime Chime 2

I’m stumped. I just replaced an old Skybell doorbell with a Ring wired pro in my new home. The indoor chime that came with the house is a Nicor Prime Chime 2 that was working fine with the Skybell. I replaced it with the ring no problem. Ring works great. It’ll ring outside, but the primechime is no longer working. I’ve switched the wires on the ring to see if it’s a circuit issue, but nothing has worked. In the ring app, it doesn’t acknowledge any other chimes.Any suggestions as to how to get it working? I can’t find anything online as they say that “it just works!” So I need to install a transformer pack?Thanks!