Display offline; pairing creates new display

I have a raspberry pi that I use as a display. It is shown as last seen about a month ago, but now when I use the activation code, it creates a new display. I want to reuse the settings. I used the recommended option when pairing. I am certain in the past that when I selected to replace a display, it did with new settings and I lost the old. Reconfiguring to what I want is a pain. How can I get taplist to recognize this raspberry pi again? I think I powered offline at one point. I also use a vpn on my router; could that be causing this?