Sorry for the inconvenience.
Where did you access the personal vault?
Such as OneDrive online or local OneDrive syn floder.
If you have tried both methods above and the same issue occurs, it is recommended to change the password of your Microsoft account to have a check.
I also suggest you change the network connection, if you are using any proxy service, please disconnect first.
Here are some commands, you could try to run them in Command Prompt (Run Command Prompt as administrator), see more please refer to "Run network commands".
netsh winsock reset
netsh int ip reset
If this issue does not go away, it is recommended to contact Microsoft by phone to verify whether there is a service interruption in your area. Thanks for your understanding.
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