FF not ending game [GAMEPLAY]

During a game i was playing recently we where behind and decided to surrender. It was a 4 to 1 vote yes we said our gg's and expected the game to end. Only to our surprise the game continued to go on longer. The game lasted enough time for us to surrender again but this time it worked so i have no idea why it didn't the first time. This is the first time its ever happened to me every other time the game has ended when i've surrendered