Do you have SteamVR launched?

When using that mod, please be aware that it is experimental, meaning that you'll have to carefuly read the installation and usage instructions, and expect that many features might be "hard" to access right away, or have issues that weren't yet fixed, or might be caused by something on your side the developer is not yet aware of.
Because of that - you'll have to share details of your issue, along with the details of your build, HMD type and the steps that you took in attempt to fix that issue on your own.