Ranked flex problem

Hello,

I am trying to play with 2 of my friends in the ranked flex queue. My Soloq rank is Gold 5, my friends ranks are gold 4 and platinum 2. Yet we can not start a match as the game says the rank difference is too high. We also tried swapping the platinum 2 account with a gold 5 account. Same message appears.

Any help on this topic would be appreciated