The loop was created, but the repeater does not appear. There are other repeaters in the document and they work. The new repeater does not work. What is the reason?
I just resolved a similar issue for myself. Newly added subfields in groups weren’t appearing, nor were newly added subfields in layouts in flexible content fields. Using the “Generate PHP” feature in the tools panel fixed it for me. It may be worth a shot for you.
Beyond that you’ll need to give us more information. Fields, code, etc. We cannot diagnose and issue without any details.