I'm trying to play in Ranked Solo/Duo with a partner, and neither of us have finished our placements. But because of our "placement ranks" it considers us too far apart to play together in anything but flex. How does this make sense?
Well your issue might be one of these
We determine premade restrictions like this: For position ranks, we use your highest provisional or non-provisional position rank For other queues, we use your provisional or non-provisional rank If you don’t have a provisional or non-provisional rank, we use your past rank If you’re new to Ranked, we use Iron IV to determine restrictions
https://boards.na.leagueoflegends.com/en/c/developer-corner/8sVyEEQ5-ranked-2019-dev-update-1
