Start the guest from full normal shutdown, not save-state. Run until you see the problem happen, then shut down the guest from within the guest OS if possible. If not possible, close the Virtualbox window for the guest with the Power Off option set.
Right-click the guest in the main Virtualbox window's guest list, choose Show Log. Save the far left tab's log, zip it, and post the zip file, using the forum's Upload Attachment tab.
I have the same problem, I updated some parameters of memory but the issue continues.
the message in the log is:
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00:07:31.117141 emR3Debug: rc=VERR_NO_PAGE_MEMORY
00:07:47.505812 GUI: User request to power VM off on Guru Meditation.
00:07:47.507941 GUI: Passing request to power VM off from machine-logic to UI session.
00:07:47.508416 GUI: Powering VM down on UI session power off request...
00:07:47.536150 Console: Machine state changed to 'Stopping'
00:07:47.567097 Console::powerDown(): A request to power off the VM has been issued (mMachineState=Stopping, InUninit=0)
00:07:47.577689 Changing the VM state from 'GURU_MEDITATION' to 'POWERING_OFF'
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It is a oracle SBC machine, dowloaded directly from Oracle. I already set my VIRTUAL MEMORY -> Paging file size = 24GB. (Windows 10)