JS Import Users Demo responds with error

[minusInfinite]

Demo: JS Import Users - https://geotab.github.io/sdk/software/js-samples/importUsers.html

When following the instructions found here - https://community.geotab.com/s/article/How-to-bulk-import-users-using-the-Import-Users-tool?language=en_US and using the provided Excel Template and ensuring the resulted data is Green

Or completing the provided form

When clicking Import Users the script responds with a JSONRPCError of -32700, which I believe is a Parse error - according to https://www.jsonrpc.org/specification#error_object

Is it possible to know why this error is being caused or what has changed from the instructions needed?
As the data requirements for adding users or drivers changed? We appear to be having similar issues displayed in the demo for our own internal API powered tools.