Guid should contain 32 digits with 4 dashes

[trevor-schmidt]

The error only happens for certain workspaces ID but the workspace ID's all are correct format.

[CodeCyclone]

There must be something interesting about your data to cause that as I see it erroring when it tries to do a cast between the Power BI SDK type and PowerShell's type mapping.
If you can do a Fiddler trace, and reply back with your Request ID and I can see if anything shows up in the trace. Otherwise you can create a support ticket so we can get access to your result directly and troubleshoot from there.