DynamoDB "explore items" showed me an error "Key not found in KeySchema."

DynamoDB "explore items" showed me an error "Key not found in KeySchema" and items didn't show up. Actually, we have a key in this table and 30+ items. We had no problem when we checked the items by using the old dashboard. This problem only occurs in the new dashboard. There was a "Feedback" button before, but now it disappeared. How can I feedback this issue to the team?