All new RAM sticks randomly cause freezing! Why?

I own an HP Obelisk Desktop 875-0034 gaming desktop.

I first tried installing a 2nd 16 GB RAM stick (Kingston) and, for a few days, every was fine. Then, my desktop began to freeze at random intervals and I had to forcefully restart the desktop to get it working. Once I removed the Kingston RAM stick, everything worked like normal.

I tried swapping the RAM sticks between the RAM slots and the issue still occurred; but when I insert the RAM stick that came with the desktop, no issues occurred so I don't think the RAM slots are bad.

For my 2nd attempt, I completely replaced the RAM that came with the desktop with 2 (Corsair) 16GB RAM sticks (totaling 32 GB), and the same issue occurred. Worked for a few days, then random freezing occurred.

The motherboard is an Edoras so BIOS doesn't show Advanced Options or XPM.

HP PC Hardware Diagnostics Windows, HP Support Assistant, and the built-in Diagnostic software have all indicated that there are "No Problems" which is obviously wrong. And HP Support Assistant says the BIOS is up-to-date.

There's no pending updates under Settings, Device Manager says the drivers are current, and neither Corsair nor Kingston offer drivers updates on their websites (not since I last checked).

And apparently, there are no manuals/spec documents ANYWHERE on the internet and HP hasn't been helpful at all.

• The PC is 64-bit and both RAMs are compatible.
• It is up to date, and uses Windows 11.
• Both RAMs are 16384 MB
• Both RAMs are 2666 MHz
• Both RAMs are DDR4

My only remaining option is to try a single 32GB RAM stick, but I'd rather not risk losing another $70+ if I'm gonna end up with the same issue.