So i was playing a game of 3vs3 and the other team the 3of them agreed to surrender still the game still continued we ended up losing. (vs shaco, darius and rengar)
Sorry to hear this but you should send a report to Riot about this instead of posting here.
It's likely they're just trolling you and saying they wanted to surrender, unless you had someone spectating/watched the replay to see it.
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