Could be fun. But.. no save? Lame. That's kind of a basic, even essential (and simple to implement) game feature. Especially if the game is so buggy that players will definitely try refreshing to see e.g. "Will this make my missing players return?" Disappointing when the answer is "Nope! Also... all your progress is also gone now!" Eh.
In case it's helpful for the dev: I noticed the players seem to go missing after they run off screen. They take a ball with them, like they're targeting some off-screen goal. (Players also regularly get 'stuck' with a ball and just stand there, until/unless you go kick it for them. Seems to happen more often when you upgrade their kick strength)