How to list all purchase lists using agent API?

Summary:

How can I use the listPurchaseLists agent API to get all purchaseLists from all users? We have a use case where a particular user needs to have the privilege to access all the purchaseLists of all users/accounts. We couldn't find a way to do this with store APIs. So we are trying to do this via agent API and then use an SSE to provide this data to the particular storefront user needing access.

Content (required):

When I try GET /ccagent/v1/purchaseLists, it's returning this error:

{

  "errorCode": "64122",

  "message": "Could not find the current shopper profile.",

  "status": "500"

}

I had tried getPurchaseList too. Same error. I had a look at agent console, where it's using /ccagentui/v1/purchaseLists to successfully get the details of given user. However, I'm not able to adapt the same query for the agent API.