OCPBUGS-59346: Agent encryption note

Author: skopacz1

modules/installing-ocp-agent-encrypt.adoc

@@ -8,6 +8,12 @@
 
 As an optional task, you can use this procedure to encrypt your disk or partition while installing {product-title} with the Agent-based Installer.
 
+[IMPORTANT]
+====
+If there are leftover TPM encryption keys from a previous operating system on the bare-metal host, the cluster deployment can get stuck.
+To avoid this situation, it is highly recommended to reset the TPM chip in the BIOS before booting the ISO.
+====
+
 .Prerequisites
 
 * You have created and configured the `install-config.yaml` and `agent-config.yaml` files, unless you are using ZTP manifests.