Hey @drugwars, before all congratulations for the great experience and game growth you acquired. I think it safe to say this project was a success since day 1.
But with all the success it would be obvious it would have people that always try to be more clever than the system and it's a good time to double down on the security. Otherwise, real players will not have a fair sensation while playing or spending time on the game.
If I may advise, you could start to implement reCaptcha v3.0, since now it's a really seamless experience and always analyze all the players vs bots movements in a quick and clean way without any confirmation or pop-ups needed to be a field or check. That way real players can keep have fun while the number of bots is reduced or even banned. This is just a short term patch I really recommend you as well to implement your own security measures like a blacklist of recurring bots and false players and other methods that make the game a safe place for all and promote a fair and fun place to be a part off.