Hi @preethi_s! As @pascal says, the intended behavior for these collection subresources is that you can create any number of them the first time you create the patient (or concept, or location, etc), but afterwards you need to interact with the subresource directly to add/edit/delete. Hopefully this addresses your issue.
FYI we recently ran into a scenario where this approach wasn’t good enough, because they needed to edit multiple concept names in a single transaction. If your scenario requires it, we’re open to you expanding the current implementation in the same way.
You can read about it in this thread: