Hey, don’t know if you found you an answer to this or not. When you posted a reply to your own question it was removed from the “Awaiting Reply” list which is where most people look for questions needing help.
Anyway. the problem is the field keys, this must begin with field_. You need to find the cause of these field keys being replaced. Also, you cannot duplicate field keys from one field group to another, so if you do copy a repeater then you need to alter the keys to be unique.
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