But every time I download the new version and apply the update. The process starts, the server reboots, but then I see the same version over and over again.
If your boot environments screen looks like this, you have two inactive 24.04.2.5 boot environments and one active 24.04.1.1 boot environment. One of the 24.04.2.5 environments is set to activate on reboot, so you simply need to reboot the system. You do not need to “apply pending update” because the updated boot environment is already installed.
After reboot, this screen should show the 24.04.2.5 boot environment as active: Now/Reboot.
Not any firm ideas. It’s possible some kind of error (potentially hardware related) is preventing it from booting into 24.04.2.5, causing it to fall back to the previous boot environment. Are you able to use a monitor or IPMI to keep an eye on console messages while it is rebooting? Maybe you can get some clue about what the issue is there.