Well, I can't answer with certainty but if you are already playing two games with someone it is unlikely they want another game with you when they placed the seek. The limitation prevents you from monopolizing all of a player's games.
If they wanted to play more games with you they would have directly challenged you instead of placing a seek.
You are not allowed to accept this seek because you are already have 2 or more games against this opponent.To start another game against this player, please challenge them directly.
what is the reason for this?