You are going to have to provide more information than that. Most of us know what a KVM switch is, but (to me at least) “AMD” is a manufacturer of microprocessors and other chips.
You don’t specify whether or not you mean the KVM switch won’t work on the keyboard port of some machine, or whether a particular keyboard won’t work with the KVM switch.
If you need help, you must “paint us a word picture” of the problem scenario. Otherwise we have no idea what you’re facing.
Write back with more information and someone will try to help you.