Invalid license error

I recently had a client let their hosting lapse, so I had to re-upload their Perch site and restore from an old database. Everything seemed to work fine, as the site is live, but no one is able to actually log in to Perch. When I try, I get an "Invalid license" error and a note telling me to add the domain to the license. I verified the domain is added as the primary domain and even tried switching to a different license and I'm still getting the error.

The site is running Perch 2.