You may be missing a file in the Secuity Health folder. My folder was empty afterWIN11 update. I ran this reinstall and can access Device Security options.
You can try reinstalling Windows Security Platform with the new update. Download from this link the folder that contains the application:
I had this turn up today after just installing a completely fresh version of Win 11 last week.
I have checked out @CharmaineK suggestion and got this (see attached image).
This is a new PC running Ryzen 5800X3D, Aorus X570 Master Motherboard, 32GB DDR4, RTX 4090 - I have a discrete (Gigabyte) TPM 2.0 Hardware Module for the motherboard due to long standing issues (stuttering that despite AMD saying was resolved is not completely resolved) with AMD's fTPM solution built into Ryzen 5000 series CPUs, which is active and recognized by Windows. Secure boot is on etc. Ran full DISM/sfc without any integrity violations or any other issues. These issues have just appeared since the latest CU installed 2 days ago (KB5023706 - Version 22H2 - OS Build 22621.1413).
Memory Integrity/Core Isolation have never been options that were available, even when using the CPU's fTPM in BIOS, a problem many others have seen - here's a link to a Microsoft support page, just updated by someone else (on an Intel 13th Gen CPU) just days ago on March 11th, so clearly not an isolated issue only impacting AMD CPU based builds: