Hello Hirdesh Baghel
Welcome to Microsoft Q&A Platform, thanks for posting your query here.
One way to do is to apply the configuration setting to name the VHDX file accordingly with the user name.
Ref: https://learn.microsoft.com/en-us/fslogix/reference-configuration-settings?tabs=profiles#vhdnamepattern
Opening each VHDX file is very resource intensive operation and also can block access to the file.
Another option is to query the FSLogix event log on the VM.
Hope this helps.
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