After failing 2 times, it should change the fail dialogue and show an "error".
Make sure Mia is in the default state when you fail (press reset on the Mod App if not)
Unfortunately, that is a system feature of the iPhone and not something I can fix.
iPhones fully kills the game by refreshing the browser whenever the RAM usage increases or there's a lag spike in the game.
There is no fix for this, and the older the iPhone, the more often it happens.
So, iPhone is not a platform that can be supported at the moment.
The next update will have a low-quality setting for weaker devices that **might** help, but I can't guarantee.