Get user accountIds using APIs

[Chris P.]

https://developer.atlassian.com/cloud/confluence/rest/api-group-users/#api-api-user-bulk-migration-get 

Using the instructions in the documentation, using these commands and passing the users first name and last name, I am able to successfully get the AccountIDs about 75% of the time.

25% of the time, I get a "None" or "Empty" string in the returned JSON payload result for AccountID.

I've gone as far as to delete and recreated a user account from scratch to see, with the same result.

In other posts, I've seen it may have been a group or permissions issue of the user making the API request, but I've also tried with admin and site-admin accounts, with the same result.

Does anyone know a consistent way to pull the users account IDs by Display Name or Email address?  Even a way to pull all users with associated account IDs (I could iterate through them until I find matching user), would help at this point.