Microsoft Surface Pro 7 Stylus not working after recent kernel update

I wasn't able to update for months prior to this update (due to https://github.com/NixOS/nixos-hardware/pull/1696) so potentially a number of things in nixpkgs or nixos-hardware could have changed if it isn't the kernel itself causing an issue. Touch screen is working. I can see the stylus devices (IPTS and IPTSD) in KDE Plasma settings, but the tablet tester shows no response. Plasma also says I have manually calibrated the tablet, which I haven't, and that the tablet is being managed by a driver, but it has said that for a while, and although the pen has been buggy (it was very jittery when hovering over the screen), it was working.