The reason for the closure is that Adobe will stop distributing and updating Flash Player on that same date, which FarmVille is built on as a game run in an internet browser, and Facebook will stop supporting flash games on its platform after that date.
Zynga said in-app purchases will be available until November 17, " at which point the game's payment system will be completely turned off". Flash gaming was the predominant way of developing online and mobile games in the early 2000s and is now replaced by HTML5, a faster and more portable coding language that developers say is also easier to frequently update. It was a farming-simulation online game, which required players to plough, plant, harvest and raise livestock, along with all of their friends. "For that we say thank you", Zynga said in a statement. It was the flawless blend of gaming plus social networking.
In-app purchases will be available until November 17th, when the game's payment system will be turned off. After the said period, FarmVille will no longer accept in-app payments and refunds. Zynga is urging players to use up any remaining credits they have before December 31, but also that there will be, "fun in-game activities to be announced soon that are created to make your remaining time with FarmVille even more enjoyable".
Apart from this, Zynga has also announced the sequel games to FarmVille, FarmVille 2: Tropic Escape and FarmVille 3 on mobile.