No label for image fields with unlimited values & can only upload one image

I have a node type with two image fields. One accepts a single value and works perfectly in the Drupad app. The second accepts unlimited values and does not work correctly in Drupad. The label does not render (just a "Choose a file" button). Also, it's only possible to upload a single picture. I would expect to see another "Choose a file" button appear below the thumbnail but there's nothing.

Thank you for your help.