CentOS

Hello
For no apparent reason, keyboard & mouse no longer work on startup when I arrive on the user login page. The keyboard & mouse work fine in the BIOS and when I select a boot OS and the startup logs do not seem to indicate an issue.
Strangely, the keyboard capital & number pad buttons work fine in the BIOS but also stop working when the user login page appears.
I cannot find a way to install the keyboard & mouse drivers. I have checked the Xorg but cannot see anything strange. I rebooted on an older xorg config and the issue remains.
Anyone have any ideas how I might troubleshoot this one?
Many thanks

Centos 7.6

CentOS 7.6 is more than 4 years out of date. You need to yum update to 7.9. Probably won't fix your issue but running old versions is unsupported. Check that the xorg-x11-drv-evdev package is installed.

Hello Trevor
After much fiddling around, it seems that the machine needed a nvidia upgrade. The nvidia driver was failing and blocking the mouse and keyboard from loading.
Many thanks your help