@George Li did you tried to run the diagnostic tests to see if it shows any errors? - https://learn.microsoft.com/en-us/powershell/high-performance-computing/running-diagnostic-tests?view=hpc19-ps
Also check if it is updated with the lastest software updates - https://learn.microsoft.com/en-us/powershell/high-performance-computing/apply-software-updates?view=hpc19-ps
Hope this helps.
JS
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