I am importing my phpBB forum data to Discourse, in the source, there are around 3300 users but on complete import, it just creates 1888 users. Did anyone face this issue?
Most importers import only users who have posts. I suspect that’s your issue.
You can look for the sql that selects the users and remove the join that checks if they have posts (though I’ve not looked at the code myself, so that might be wrong).