First, please check if it's possible to update your device to at least Android 11.

Unfortunately, the Share function is currently unavailable for devices running Android 9 or lower, Xiaomi/Redmi/Oppo devices and some other devices running Android versions lower than 11. This is caused by technical limitations of Android and by limitations of the operating systems of the devices themselves. On such devices this function wouldn't work properly and wouldn't grant the offered reward.

In future updates, our team will try to find a way to add this feature on devices that don't support it at the moment. Right now, you can only use this function if you play on a different device.