I've encountered some problems using POST /workspaces/{workspaceId}/timeEntries/user/{userId}/entriesInRange
It works only if I ask for my own userid, but when I request data for other workspace users - I get 403 - forbidden - how can I change that ? I'm using account within admin group
That endpoint is used for the timesheet functionality and does not support users other than yourself, even if you are an admin of your workspace. You can however use the SummaryReport endpoint which will give you time entries in requested range, and you can set the input parameter 'me' to toggle between your and your team's entries:
https://clockify.github.io/clockify_api_docs/#tag-Summary-report