/usr/bin/nvidia-modprobe: unrecognized option: "-s"

I also faced issue after updating my driver to 455.45.01, above instructions works, This would also solve the issue, without adding PPA.

wget http://developer.download.nvidia.com/compute/cuda/repos/ubuntu1804/x86_64/nvidia-modprobe_455.45.01-0ubuntu1_amd64.deb

and then install with

sudo dpkg -i nvidia-modprobe_455.45.01-0ubuntu1_amd64.deb

I had exactly the same problem after recent update to 450.80.2. In my case the following got the issue resolved:

1. Add / enable PPA http://developer.download.nvidia.com/compute/cuda/repos/ubuntu1804/x86_64.
2. sudo apt-get update.
3. Optionally verify candidates are available: sudo apt-cache policy nvidia-modprobe.
4. sudo apt-get install nvidia-modprobe=450.80.02-0ubuntu1.
5. Remove / disable PPA http://developer.download.nvidia.com/compute/cuda/repos/ubuntu1804/x86_64 if you do not intend using it soon again.